I've had a really rough last two years, and through online research I discovered I have many of the symptoms of BPD. However, I'm seeking advice because 1.) I know that self-diagnosing yourself based on the internet is not very healthy or useful, and 2.) I wouldn't be able to afford medications even if I went to see a therapist or something. I'm not even sure I could secure transportation to/from a therapist anyway.

- I don't wish to harm myself or commit suicide, but sometimes I snap rubberbands on my wrist to calm down and when I'm having a panic attack I feel like bashing my head against a wall, and I have, but that rarely happens. Maybe once a month.

- I have EXTREME abandonment issues, although only with one person. I disregard my other relationships and only focus on clinging to this one individual, in a way that is decidedly unhealthy. During one panic attack, I told this person I would kill myself if they left, but I didn't really mean it. If I am left alone overnight in a house/apartment, I find it very hard to sleep.

- I categorize people into being entirely good or entirely bad. If I feel threatened by them or if they make a bad first impression, I hate them forever and nitpick everything I hear about them. If I hear their name, I make a disgusted facial expression without even noticing I'm doing it. Talking about someone I dislike can cause me to slip into a mood where I brood and pout for hours afterward, even though I really don't want to. I try to get over it and go on with my day, but just can't. Then I feel stupid for getting so upset. On the other hand, if I like someone, I idolize them and even if they later do things that disagree with my morals, I don't care.

- I have "identity disturbance," in which I alternate between feeling like I'm a rotten person and feeling like I am superior to everyone around me. When I feel rotten, it is usually due to me noticing the behavior mentioned above, and thinking I am a judgmental ***** because of it. In general, I prefer to make friends that I feel INferior to, actually.

- I am very paranoid about what other people are doing. Examples include thinking I'm being cheated on, family members talking **** about me, etc. Etc. I don't care about how my classmates/peers perceive me though.

I am in college and I have tried to dismiss all of this as just college-related stress that will pass, but something in my gut tells me there is more to it. I have also had major problems with my family and my relationship, and I feel like my behavior could've caused those problems, rather than the problems causing my stress. I don't know where to go from here.

To my untrained ear you do sound Borderline, but I think of emotional 'disorders' as being on a sort of spinning wheel with the diagnoses on the spokes. They can overlap and they can change and they can wax and wane (and you can even say, who out there doesn't fit in there somewhere). Even doctors and therapists will often admit that it's a crapshoot, and will decide based as much on what medications work as on observation. They change diagnoses too. They have to have one in order to submit insurance claims and report to the state if they are funded.
So, try not to dwell on what to call yourself. This isn't deciding between schizophrenia and bipolar. You come from a dysfunctional family, right? Sort of out of fashion these days to be just neurotic. You do manage to stay in school and take care of daily routines (I assume). I wouldn't call your anxiety over being left by the person you are in a relationship with part of abandonment issues unless you've had this with a lot of family, friends, lovers. And so on - what is a panic attack, what is identity disturbance, how hard you bang your head, I won't address each one.
BPD is so difficult to treat, so is a diagnosis I would want to avoid. Many people with it are just too good at talking circles around themselves and any therapist, and they resist anyway, even when seeking help. You sound like you would benefit as much from a good group as you would from individual therapy, since you have a lot of insight and summarize well. No such groups on campus? No college health plan?

Thank you for your answer! There is a women's health office that offers counseling here - I think students can have three free "sessions" or something. I have gender identity issues as well so I am a little put off by the "women's health" part and would prefer if there was just a plain ol' counselor to talk to, but even still, I am scared and I feel like I would lie to them under pressure even though I really want help. I guess I need to go try instead of assuming the worst about myself, though.
I have absolutely no friends on campus here and am not aware of any specific support groups.

To answer some of your curiosities: I only speak to one member of my family - my mother. We had serious issues in my childhood, but we smoothed things over now. She had OCD but it mostly cleared up when I moved out. The rest of my (estranged/extended) family are the type of people who think all mentally ill people are "faking" and "just being lazy," which just adds to me feeling hesitant about this and guilty. I know for a fact that my father has made up horrible lies about me and tells them.

I considered my relationship issues "abandonment issues" because he has tried to leave me three times and I made a huge scene all three times and somehow still have him. He has cheated on me and hurt himself and done other bad things but still I can't function without him. I've lost many friends because they think our relationship is "toxic." He feels manipulated by me, but really when we try to talk things out I just end up making a bunch of sacrifices and letting him do whatever he wants.

When I have panic attacks, I cannot breathe and my heart beats fast and I dry-heave and want to curl up in a ball. During/afterwards, I feel empty or dead inside and will stare at a wall for hours. I don't remember how hard I bang my head, but I've never drawn blood.

I am making straight A's in school although it's hard to manage, and if I am left alone I find it hard to eat properly and sleep properly (but I have a roommate so I'm usually okay.) I will have periods of staying up all night cleaning and organizing things instead of doing work that should be done.

I agree about the sound of the name of the clinic, but also agree that it is worth checking it out.
What are you scared of by going? Falling apart by opening up? If you tell a (good) therapist your fear, she can keep it on a practical level. Rather than delving into the past much and searching for illness, you will work on the present and future, ways to cope (trite but true). Short term therapy works that way anyway, and most is short term these days. And she can refer you for more counseling if needed.

What about insurance; don't most schools require it or include it in tuition, or am I showing my age?

What I'm trying to say about terminology is not to get too much into it. Abandonment, panic attack, words used to take notes. They don't define you, nor are they particularly useful for YOU. They can even add a stamp of permanence to how you see yourself. 'Not liking being alone' and 'freaking out when walked out on by a lover' are just that. You could finish school, get a job, and find that you want to be alone after work. You could meet a faithful man and not feel abandoned at all when he says he has to go for a week on business. As you get older, you change, UNLESS you really have a mental illness, then it's a lot harder. So assume at your young age that you don't, and leave the terms aside for now.

Joy is right on the money. Stop labeling yourself and looking for a diagnosis. We're all a little weird. It sounds like there are some good things going on in your life too. Why not pat yourself on the back for those?