Is this possibly pregnancy? I'm scared.

I'm sexually active, I had a "period" about 7 weeks ago but it was weird, there was blood a very small amount on the first day but I mean very small not even a fourth of a pad and then for 3 days straight just brown stuff that was gross and then like a little black at the end like dark brown. Now I'm 21 days late, I'm not regularly on the pill. I dont have any throwing up but I have cramps, sharp ones mainly and have for about 3 weeks on and off. Moodiness, major moodiness and anger I get triggered really easily over small things now but then will be all happy and fluffy 1 minute later. No other symptoms, boobs might be slightly more sensitive but not noticeably. And my sex drive dissapeared this past week, I usually have a super high one. A good amount of discharge more than normal and MAJOR BO like I've never had that but damn I stink but idk if that has anything to do with it. What do u guys think? OH and the thing is i would have to be 7 weeks along as that's just after my boyfriend went out of town.