Discharge

About a month ago after having sex with my boyfriend with a new brand of condoms, my vagina was swollen and hurting. We thought it was condom but I also noticed that I had a red rash around my vagina and yellow discharge. It went away after a week so I didn't go to the doctor. However, the yellow discharge is back and it's a lot of it. My vagina is also feeling irratated like it felt before. What could this be? I also just remembered it happened again after having sex with him the other day. It also hurt when we were having sex and that doesn't usually happen.