Hi there, I am 21 years old, female, and I'm around 5'4" in height and 104 pounds in weight. I'm trying to get down to 90 pounds however, and for the last 3 weeks I started off with a diet of 500-550 calories a day, but I lately lowered my calorie intake for the last week or so to 300-400 calories a day.

I personally have read a lot of arguements against the "Starvation mode" and I just want to know if eating this little for a few weeks is going to help with the weight loss? I also work out everyday for 2 hours.

The reason why I have restricted my calorie intake as well was because I hit a weight loss wall for months. I was stuck around 110/108 pounds and it was bothering me, no matter how hard I worked and no matter how well I watched my food intake.

You hit a wall because you're body at 5'4 is not designed to be 90lbs. Even 108 is on the low end. I am 5'4, 30 yrs old and up until 2 years ago I was 85 lbs. I was ill, had no energy, constantly dizzy, did serious damage to my kidneys, and completely shut down my metabolism. When family stepped in and convinced me I was facing certain death I got help, for my husband, my parents, ny children, but mostly myself. I have spent the better part of my 30 years being miserable. You think you will be happy at 90 but you won't. You'll just want to keep going. You'll never see a number on the scale you feel good about. It is truly a miserable and isolating life style. I have lost many friends because of my disease. It is not something to toy around with. And starving yourself will only shut down your metabolism and make it harder and harder to work out. Eat healthy and exercise. Don't get into this life style. I had not planned on spilling my guts in this answer but this is something I am very passionate about and very personal to me.

I totally understand about not being able to have the energy to work out because I have been feeling a drop in energy lately, but it IS getting to become a comulsion. I WANT to be 90 pounds, I KNOW I have a problem, and I'm sorry, but this is what I want to do.
I tried eating healthy and exercising for months but I was stuck at 108 pounds and it sickened me because I felt I worked so hard and got nothing in return

Compulsion*

How old are you?

21 as stated in the original question.

That level of intake will cause you serious ( very serious) health issues, even short term and worst as you foolishly do this longer term.

Proper intake, with a proper balanced meals, and proper work out. Your weight goal sounds unrealistic and unhealthy, Have you been following up with doctors for blood tests and health advice

Yes sorry, I saw that after I asked. I have been in your mind set and no one could change my mind. So probably nothing I say matters. But please believe me that once you realize a number doesn't define you, you will be a much happier, more productive person. Don't let it get out of control like I did. Don't let it carry on into your marriage, children, etc. I have lost a lot of years that I would give anything to have back. Talk to someone. A doctor, a teacher, a friend. Don't let this take over your life or go further than it already has.

Yeah, absolutely, mamof2boys. I am speaking to a few friends about it. I know I have a problem, I suffer from OCD as well, so imagine the combination and its hold on me in this "diet". I literally obsess over my weight all day long, and I want it to stop
I just want to look good, and I tried even not weighing myself for a few months. I just went with my looks and thoughts based on myself from the mirror. But it became a problem when I continuously saw myself as fat in the mirror, and convinced myself that a # would be more accurate and pleasing
But as you wisely said, this is not the case.

I know that feeling. Waking up in the morning excited/scared to weigh, planning out everything you do all day based on your food plan. It's so consuming. And let me just say, while I am better and I choose to live healthy now, that does not mean all those thoughts and fears disappear. I still look at old photos and catch myself wishing I still looked like that. But I had to understand my perception of myself was so wrong. When I was 85 lbs not one person told me I looked good. Everyone looked at me as if I pained them. Now I get so many compliments on how great I look. I have to believe everyone else sees me as I am, and I do not. So so hard. But yes, please, find someone who can help you. Don't let this become you.

That's EXACTLY what I am going through, in all honesty. I wake up, and immediately start measuring my food before I even eat it, and then exercise like mad to burn it all. It's sickening and disturbing me to no end.
I am trying to stop, honest to Odin I have. I stopped working out once for nearly 2 weeks, but I got severely depressed, and working out just makes me feel really good. It's the only medicine I have for relieving my depression.
And I'm just trying to shed off the last few pounds as best I can, and getting over this darn weight loss wall. I just want to do that, and go back to a normal life is all