My vagina hole hurts when i get pee on it after sex??

Okay, so I had sex with my boyfriend and when he put it in (no condom) it hurt slightly but nothing really noticeable. But when he put on the condom and even with lube (both condom and lube we use all the time) my vagina hole around the entry started burning a little bit. The sex wasn't rough either. So after sex I went to go pee and when I did it dribbled on my vagina hole a little bit and omg it burnt soooooooooo bad. It wasn't my urethra or anywhere on my clit or lips just when it got on my hole. This has happened to me before rough sex or not and it went away on its own, but what could be going on?