Today's the last day of my period, but I'm never nauseated and all my symptoms go away normally by the fifth day. About two hours ago, I started feeling a little nauseated driving home from school. I ate a little when I got home, hopped in the tub, got out. And I feel incredibly nausated, I'm gassy, I just had a bowel movement, and my eyes feel droopy and tired. What could be wrong?