My boyfriend has just told me that he's had a rash on his penis that has popped up two times in the past 2 months. Each after we've had sex. We've had sex in between those two times that he had the rash, but he's starting to get worried that it could be a sexually transmitted disease. He's not circumsized, and I've been reading, and it says that possibilities could be starting from a yeast infection all the way to of course a STD, to just irritation from having sex. I'm not having any problems. I'm fine. Should he go to the doctor anyway?