A lot of times when I have an erection (usually after ejaculation) my penis can get really sore. Sometimes if I get another erection anytime during the same day its really sore. I'm not being too hard on my penis or anything, just regular masturbation or sex, and its more of an aching. I know a lot of people who can go one time after another and a lot of times for me, it aches to get another erection anytime in the same day. I'm wondering if I should check with my doctor to see what he says. Any suggestions?