Hello I have been feeling nauseous everyday for over a week. I am not pregnant i am positive of this. I gag and try to vomit but nothing comes up , I m starving but if I eat I will throw it up, I have headaches , I sweat but am cold at the same time, I m tired but can t sleep , I get dizzy , I have have slight diarrhea . No fever . What is wrong with me ?