Long story short, I noticed two hard lumps in my penis a few weeks ago. I saw a doc about it and was referred to a urologist. His best explanation was that I experienced blunt trauma to the penis (think having it slip out during sex and then jamming into the girl; you know you've done it lol), which caused microtrauma and a small amount of internal bleeding. This blood then hardened and turned into plaques which are the lumps. Sounded crazy to me at first, but it made sense after he explained it. At least they weren't tumors or any of the other horrible things I was imagining them to be.
He then told me that he wanted me to take something and whipped out a prescription slip. I was surprised to see him write l-arginine on there and tell me to go to my local GNC. He said it is used to break up plaques in hardened arteries and that it could be used for the same purpose here. Just thought some of you would be amused by this