Can't understand why my body insists upon hating me..

I'm extremely tired during the day, can barely stay awake during class, finally get into bed for sleep.. and I'm wide awake. I feel under, and have a desire to eat... But when I do I feel nauseous after a couple bites and struggle to eat enough for basic human survival.. If I get into the habit of Niort eating I'll develop anorexia again. I'm usually incredible with remembering dates.. Appointments, test dates, assignment due dates, work schedule... Recently I  haven't been able to keep anything straight in my head. I just remembered tonight (Thursday/friday 1am) that I have a presentation due on Monday. It's not like me asst all to forget about an assignment or leave it till last minute.  What's going on with me.