Another panicked "Am I pregnant?" question, but I'd appreciate feedback.?

My boyfriend was inside me, but didn't ejaculate and hadn't ejaculated previously that evening. There was pre-ejaculate, though. We didn't use protection because he wasn't going to be finishing in there. I was at the ending phase of my first infertile period of my menstrual cycle; eight days, I believe, in a 26 day cycle. I have had what have seemed like two periods since then, 26 days apart exactly, but I don't know if they were actual periods or just bleeding. I took one pregnancy test that was negative and don't really feel any signs of pregnancy unless I worry and think about them too much--I haven't had morning sickness yet--but now I'm a little worried that my breasts might have gotten bigger. I'd be about ten weeks along if I were pregnant. If you've got any insight as to whether it's likely that I'm pregnant, I'd be very appreciative. Thank you.