Anxiety keeping me from going to school

I have a diagnosed anxiety disorder and I honestly believe it keeps me from wanting to go to school. I find myself going only at the last day before I would have to be dropped from the class and I've noticed it's getting so bad that I've failed some classes. I honestly don't know what to do. Every quarter I tell myself I'm gunna do better and then I basically have a panic attack when it comes time to leave or I have this overwhelming wave of anxiety before I have to go. What should I do? If I go to a doctor is there some kind of medication I can be put on to help with this feeling? Has this happened to anybody else?