TeenHelp - Cramps and might be pregnant?

Okay so basically, as of the last time I posted, I asked the guy and he said he didn't remember if he had came in me or not, and it was unprotected for those who don't know. Last day of my period, if that makes any difference. In any case, I'm going to take a pregnancy test, he's buying it, but the thing is I'm getting awful cramps. Which is not helping my already really worried self. I haven't been making the smartest decisions knowing that I may be pregnant, for example, I got drunk last night, and I've been smoking weed nearly every night, as well as I still haven't fully kicked my cigarette habit.

Anyway, question is, should I worry about these bad cramps I'm having considering there's a chance I could be pregnant, and could it be because I got drunk last night? I know that actual pregnancy symptoms wouldn't even be showing up at all yet, but if I was and the alcohol or other stuff did something, could that cause this?

I know it's stupid to keep worrying when I don't even know, I just can't help it, I'm seriously stressing out way too much over here, but I can't help it.