Chances of being pregnant?!

Okay I know people say dry humping is an unlikely chance of getting pregnant. The last day of my period was on Feb 3rd and that day me and my boyfriend were messing around. He was naked and I had my underwear on. He didnt penetrate inside me at all, just the outside. I know theres always precum but I didnt feel anything wet on my underwear. And three days later, we did the same thing again. Two days later I started getting headaches and felt tired. And now I been been breaking out, getting light cramps, gas cramps, dizziness, constipated, feeling weak, feeling bloated, and this morning I started gagging my breakfast..I didnt feel like eating it. I think my boobs are starting to hurt too. And I never really felt like this after a week and a half of getting my period. I get some of these symptoms a week before my period but my period is not even until 2 weeks from now. Why am I getting these symptoms a week later and we didnt even have sex? I know he didnt ejaculate and im pretty sure I didnt feel any wet precum on my underwear. Is this even possible?! I think im just paranoid and its all in my head.