Am I pregnant?! Or is this something else? Please help!?

I have been with my boyfriend for only a few months now. I have always had irregular periods so I'm used to getting 2 in a month or even 0. I had a period May 15-20 and then another soon after in June 1-5. I had sex with my bf on the 6th. I am not on birth control. When we were having sex the condom ripped apart. He came out and I was sitting there with all of his semen inside me. I understood that it was an accident so I wasn't upset at him. After I used the bathroom I just went to bed. About 12 days later I was using the bathroom and noticed a tiny bit of pinkish blood/discharge on my underwear. I thought I started my period again But that tiny amount of blood was all that ever came; I never had a full period. I didn't think anything of it until about 4 days ago the 18th I started to feel different. I am feeling sick; just not right. I don't have an appetite but my stomach has this horrible empty feeling through out the day. I will eat but it doesn't help the hollow feeling. I have pain dull cramping in my uterus, My stomach feels sick after I eat, My breasts are tender but don't quite hurt yet, I've been super sleepy, run out of energy quickly at work, my hip muscles are sore, I started breaking out, i have more discharge than normal and I'm more easily stimulated down there. I started thinking about how the period I had in June was around the time that I would have ovulated if my periods were more regular. Then I thought that maybe the increase in hormones before and during while I was ovulating were enough to trigger an irregular period. So by the time my period ended and I had sex, my egg was still coming down the Fallopian tube and was fertilized by my bf's sperm. I'm not sure if that's what happened but I've never been pregnant before so I'm not sure. I don't want to wait for a missed period cause they are so irregular. What should I do? Could I be pregnant? Or could something else be behind this? Thank you to anyone with good advice/info!