(Please Reply) Is It All On Me?

I remember when I was younger, I wanted to get myself a job more than anything. I would dream at night about being part of the working class, and earning soime extra money for my family. I was unemployed, just graduated high school with all honors classes. I had a clear life plan and a sense of direction with what I wanted to be in life. I was at a point where I finally felt okay, I was a happy. A bit of a late bloomer, but I still had a clear sense of direction, with a good head on my shoulders.

I ended up getting my first job at the local dollar store, for the first few months everything was roses.
Now I'm 19, and I'm clinically diagnosed with Generalized Anxiety Disorder.

After a particularly hard day at work, I landed in the hospital. My body went numb, my brain deprived of oxegyn from hyperventilating, stressing about tomorrow, and how poorly I was getting my job done. Since that day, my anxiety hasn't changed. My diet and my sleep schedule have suffered dramatically, my world view is overly negative, and I feel as if I can no longer trust anybody. I'm constantly looking over my shoulder, afraid that everyone is out to get me for no good reason. I dread even the thought of going to work in the morning, and I've lost all sense of myself. Nothing in life brings me joy anymore, and I feel as though I am worthless to the rest of the community. As for people, I don't have a relationship with anybody (outside of family). I can't seem to tell when someone is joking with me, I feel like everybody at work has an alternate opinion of me, that they're hiding things from me. I've noticed I've become testy, and take everything so seriously. I used to feel like I was safe, and that I was loved and respected. But now I can't even go to bed without crying myself to sleep at night. I feel a total absence of compassion and respect, from both customers and fellow employees. I can't stand being told what to do by anybody, anymore. I despise all customers, and feel as if they see me as some kind of punching bag, so they can do or say whatever they want to me, and I can't do anything about it without risking my career. I'm embarassed of being a cashier, because I associate the position with powerlessness, vulnerability, and the feeling of being mentally destroyed. I hate everything about it, but despite my family begging me to quit, I would feel like I was a digrace if I do so, and I wouldn't be able to face them the same way. This is not who I am! This is an empty husk, of the lively, loving, confident and bold person I once was, and I often blame myself for feeling this way. But despite all of that, something is telling me that if I was in a healthy working environment, I wouldn't go from completley fine to a clinical diagnosis in six months.

Is this all on me?