any sperm in the pre-ejaculatory fluid?

My boyfriend and I have never had sex, but we did dry hump. I had on underwear and basketball shorts and he had on boxer briefs and sweatpants. He did have some pre-ejaculatory fluid on his boxers, which I did touch, but he did not ejaculate at all for a week. I read that because of that, there should not be any sperm in the pre-ejaculatory fluid. Also, I'm not sure if I touched my privates while fixing a wedgie. Lately, there's been a lot of stress and I've been feeling a little nausea and headaches and eye irritation, but I'm also scared that I could be pregnant. I had my last period on February 14 (which was unusually early because the one before that started on January 1) and I'm not sure if the symptoms I'm showing are pregnancy symptoms or just signs my period is coming, and I have allergies too. My discharge is clear and I have been getting some cramps (same area as before my usual period). Could I be pregnant, or am I being paranoid about nothing? Please help. Thanks.