question: Hello doctor, I have a sore at the middle of my penile shaft. I believe this was due to excessive masturbation and having sex when it was sore and hurting, to begin with. It seems like it is healing up, but I want to make sure. There has not been pus, discharge or pain from peeing. Just the irritated spot has been sore. The skin has turned dark there as it is healing I presume? I have been having sex with the same person for over two years so I do not think it is anything she gave to me as she is clean. I am just hoping this is not some sort of STI.