I am a 21 year old women who has been with the same guy for almost a year, we have been completely faithful to eachother and we are both clean of STD's i have never had a yeast infection or a UTI and everything has been good until the last week, after sex the other night (tuesday) i was in pain and my boyfriend noticed that my "lips" were swollen, we figured it was that i just got to dry or that the sex was to rough, so we picked up lube, we had sex a few more times that week and then again last night (sunday) and after last night it was swollen again but not as much as last time, it wasn't to dry this time nor to rough, we always use a condom and i am on the pill. Any ideas what the swelling is from?