I Recently Started Having Some Health Complications. Well Sort Of.

I recently started having some health complications. Well sort of. Early this morning I had been faced with an unu pain in my stomach that later resulted in me having diarrhea. I decided it must of been something I ate. Then I started puking. I knew something wasn't right after this. Now I have more weird problems: a constant headache, slight fever, dizziness, and very little energy. What could this be caused by?