What's wrong with me?

So lately I have been really stressed out with school. I have been absent a few days here and there because I have to go to my specialist for my stomach because I have a digestive problem. Anyway I have alot of wok to do, and i have to force myself everyday to get up and do it. Th teachers are buts and dont help me either! I mean I think I'm burnt out, or really stressed. I also get really bad anxiety and freak out. Anyway lately all I want to do is sit in my room and play my guitar, I don't care about my grades anymore. There not slipping terribly but I have to force myself to get anything done. I feel like my teachers and the adults misled me. They said freshman year that if u don't get into advanced classes,and have atleast a 90 gpa then ur a **** up and will always be one that works at mcdonalds pretty much. So my whole high school career up intill now(I'm a junior) I would run that whole thing in my head and work myself so hard IDE freak out about my grades and get anxiety. Now I realize that just because u get 80s ur not a **** up and ur life won't be screwed.I think I had an apithamy that there is so much more to life, and it's okay to make mistakes because everyone does. I feel like that, and the fact that I'm goingto community college-for a year because of money makes me have no motivation. Sorry that this is long and all, but do u think somethings wrong with me for having this realization and not caring so much in school?What's wrong with me?
You're gay.