What Causes Small Red Bumps On The Penis?

I have had small red bumps on my penis every since I was a child. The red bumps don't seem to be on the end of my penis or the upper half, but towards the base and on the scrotom, there are red bumps. Just until now, I'm 15, they, or at least my scrotom and penis, have started to itch like crazy. I don't masturbate nor have I had sex. What do I do?