Can Someone Explain What's Going On ?!😐

Guys i really need help i have been having unprotected sex lately but my man pulls out everytime but last week i got cramps and i dont know if it was because i had gas and needed to poop or what but it hurt but once i would pass gas it would stop untill i needed to again and aside from that my boobs have been starting to get a little sore and i also woke up one morning with discharge leaking down my leg. I took a pregnancy test and it came out negative but i'm just really anxious and paranoid. if someone could please help me figure out what's going on. By the way I'm supposed to get my period in 12 days