I have noticed that there is sometimes a redness that occurs on my penis. I had this checked out by a doctor and he said it was a regular rash and that it should subside but it has not. I've also noticed that I've been going to restroom more frequently and that I am not able to produce a powerful stream, even when I force myself to sometimes. Other times, when I am able to force out a powerful stream, I feel a pain, almost a burning, at the tip of my penis. There's also a little bit of a smell. What can this be?