I thought my frequent changes in mood and forgetfulness was just normal until it got worse. Before, it was just small things that were hardly noticeable. For example, I would walk into a room and forget why, and when a certain thing was said, my mood would change completely. Now, I forget everything important that had happened a couple of days, or even weeks ago. Sometimes I look at myself and think its not me or I seem smaller than I thought. I am only fifteen, and I know these things shouldn't be happening, but then again, it could all be in my head. Sometimes the changes in mood and forgetfulness can be so frequent that it overwhelms me and I don't know what to do.

It's really not possible online to know if a 15 year old (girl, I assume?) is just a typical teen with hormones all over the map and the mood changes most teens are going through, or if you are indeed developing a real illness. Forgetfulness can be a sign of too much going on in your life, depression, or just the same forgetfulness everyone goes through. At the other end of the spectrum it can be something rare and serious. How dramatic is the 'that's not me' when you look at yourself? We all have moments of that, so again, it all depends on whether this is the usual feeling or a more serious sign.

Have you told any of this to your parents or parent? Has anyone mentioned anything about your behavior? What others notice is really the best mirror, unless your inner thoughts are teeming with scary feelings and ideas.

You assume correct and I have thought about it being teenage hormones. But, when I have a feeling of 'this isn't me' it's very frightening, at first. I find myself grabbing my hands and feeling my face. But, after a minute or two, I start to calm down. I've taken therapy, and I told her about my constant changes in mood. She told me to try and find out what has been causing it and to try and look for a pattern. I did as she said, and it was a bit difficult at first, but I eventually found there wasn't really a pattern. I've tried to find out what's been triggering these changes, but so far I haven't been very successful. Close friends have noticed and I've talked to my parent about seeing a psychiatrist, but he says now is not the time. He has too much going on. My best friend actually recommended I see someone, but I would feel more sure if I can get a reccomendation from someone who knows a bit more about it and someone who isn't stilll in high school.

Tell us in more detail about what your friends notice (if you are willing).
Feeling yourself in a panic when you think you are not you is getting a bit serious.

When you say 'a bit serious', should I be worried? They've told me I get aggressive, but a minute to a day later it'll be as if nothing happened and pretty much everyone notices my depression.

And how do you see yourself when they tell you this?
(Keep in mind that we aren't there, don't know you, and it's really tough to 'see' the whole picture.)
Thinking you are not you is wrapped up in depression. Some say that you 'dissociate' or 'go into a dissociative state' whereby you feel strangely detached from everything, or that nothing is real, or that you are not you. But don't think of it as some total weirdness, because it's really you wishing you weren't you for a while, so that you don't have to face what's bothering you.
In rare cases it can be an early sign of schizophrenia, but for now just assume that you are part of the vast numbers of teens who are depressed and not facing your feelings.
Lashing out at people must have some basis in some pent up anger or hurt. Then you get depressed - of course, who wouldn't? You don't really want to be like that.
So tell us what happened in your life, if you can. And maybe go back to the therapist. You need to find out when and why this started. 90% of that job is yours; the therapist can only guide you and offer insight and solutions.

When they told me, I didn't know what to think. The cause could be that I've been abused in every way but physically. I had to see a therapist because someone had told our school principal about me self-harming, but now that school is over, I have no way to see a therapist because my parent can't take me to see one.

Yelling, demeaning you, etc? Who?
You can't see a therapist because your parents can't afford it/don't have insurance for it, or just don't want to?

My father, grandmother, brother, and uncle tell me I'm lazy, I never do anything, I'm only worried about myself, I'm ungrateful. Things like that. My dad can't take me because he has a lot on him right now. We live with my grandmother and he's having to pay for pretty much everything because she quit her job. Then again, when I ask for anything, he makes a big real about it and complains I'm spending all of his money.

It sounds like you are the scapegoat and the "safe" (i.e. easy) person to blame for everything, the one to demean, since the adults don't dare demean each other.

Do you have chores assigned and do them when you are supposed to? How are the grades in school?

That's not unusual sounding, so there must be something that made you cut.
What do you ask your dad for? (I'm 66 and in those days, no one got anything, so I'm only marginally aware of what teens expect these days.)
What happened to your mother?
Do you feel that you can understand a parent who has huge money worries?

They expect me to do one thing every single day; wash dishes. And, if they don't want to do anything, they'll just put it on me or my brother. Grades are terrible, being as I can't remember important things and fail most of my tests.

I'm starting to get a bit confused myself, so I apologize if what I say makes little to no sense. I just ask to go places, and sometimes I'll ask for something I see that I like, but I don't expect him to get it. I just ask because it interests me and I'm a teenager. I ask for a lot, but when be says no, I don't get upset and start throwing fits. I just say okay and that's it.

If you fail most of your tests, what are you hearing from teachers? What is being done about that?

I'm failing three of your classes. Two of the teachers are helping me and I don't think the other even knows my name.

"I'm failing three of YOUR classes"? Do you think someone here is one of your teachers or is at your school?

Someone said you self harm. Do you?

It sounds like you need an adult to speak with, perhaps a teacher or clergyperson or friend - ? Is there anyone in your life who is like that?

Marie, are you out there? Please write something.

“Sometimes the changes in mood-” Does this include anger? If yes, than it might be because of the emotional abuse, maybe it's something else. I don't know.
Do you get enough sleep? Sleeping is important for your memory. But I think that you still need to see a doctor.
“-everyone notices my depression.” Do you feel depressed, or it's just what everyone says? Depression causes forgetfulness.
Forgetting things like after you walk into a room is VERY normal. It happens to everyone. Things that we remember in a second and forget in an instant happen because these information are stored in our short-term memory (For example, you walk into a room to get a pencil, and when you get there you forget for what reason). If it happens constantly then who knows.
Stress too causes forgetfulness. I would think all the pressure from home and school can be a problem, can be the reason for stress, if you have any.
Do you forget familiar faces? Events form the past? If no than, and let me just say that this is a probability only, I know that it can be anything else, your forgetfulness may be the cause of emotional abuse you had. If yes, you forget familiar faces and past events form years ago, than it's anything else.
I made snap judgments here; NOTHING I said here should be considered as 'for sure' an answer to any of your questions. Only a doctor can tell you for sure.

You need to see a doctor somehow, if you have any questions than PLEASE ask US.

When I said your, I meant FOUR. It was an autocorrect thing and I didn't realize until you mentioned it...

I apologize, I haven't been able to reply in a while... Too much going on and I honestly had forgotten about this.