Pregnant? Maybe? No? What?

I was supposed to get my period a week ago, and a few weeks ago I had unprotected sex with my boyfriend. I took 2 tests they both came back negative, I have felt like throwing up and have a stomachache and have cramps occasionally. And today I've been really hungry, I've eaten all day and I'm still hungry. I don't know what's goin on but it's not normal for me. What should I do? Help!!!