Just a quick thought for you. The others are right, you could call around and ask about sliding scale fees. However, you mentioned your University. Are you currently a student there? I believe that most colleges/universities have counselors there. And depending upon the school you are at they may or may not have someone on staff that could prescribe as well. Either way, you should at least look into the counseling part. And I'm sure that whoever is there could at least provide helpful information on where you could go to see a doctor for medication or lower cost medication.
Also, I know that you mentioned that you don't have many shifts yet at work. Until your hours build up, is there somewhere you could go (depdending upon your health) for a few extra hours a week to volunteer and keep you out of your stressful home environment? Or perhaps you could even spend more time at your local library either doing homework and picking out interesting book(s) to read. This way you could be more relaxed and take care of yourself physically as well.
I'll keep you in my thoughts.