Greetings, I had some very stimulating sex with my girlfriend last night. When I woke up in the morning, the shaft of my penis was swollen and had become discolored close to black. The tip is still Caucasian. When I urinate, everything appears to be normal. It is sore, but nothing that isn't natural. The only thing that is abnormal is the color which has turned from white to black? What to do? P.S. This is the first time this has ever happened to me and I am now 46. Thank you for your time and consideration. MJ