Hey, this morning i woke up and there was a painful, hard, red lump on the shaft of my penis. It is something in the skin. I was unsure if it was some sort of spot and attempted to squeeze it and some sort of pus came out and then only blood. This has caused blood vessels in and around the lump to burst. It is about the size of one of the plastic heads of a clothe pin. I dont beliebe it is STD related and there's only one lump. It is much more painful when it's errect.Any thoughts on what it is and how to treat it?