I always have very irregular periods and around the 14th of December, I had some bleeding and I thought it was my period. It stopped a few hours later. The same happened about 2 days ago. I only had sore breasts for one day and it was about a month ago. I've been feeling a lot of cramping for the past month or so and bloating as well. I had sex last night and it was very painful, in my lower stomach area. Never had unprotected sex. One time on Dec. 7th we didn't have unprotected sex but I thought pre-ejaculation might've made contact with my vagina....I waited until this morning to take a pregnancy test because I didn't wanna test too early and it came out negative. If not pregnant,what could this be??