My boyfriend and I were having unprotected sex, the thing is that when we were just starting (probably less than 5 mins into it) the skin on his penis (not circumsized) ripped and he spilled blood inside of me. The last time I had my period was around march 23-25, now I'm late. I decided to take a pregnancy test and it came out negative but I still get nausea after I eat. I don't have tender breasts or feel tired. But is there a chance that I could have gotten pregnant when this happened? I also sometimes get cramps but no period. I'm worried.