I few weeks ago I noticed a small white head looking thing on the shaft of my penis. I did some "research" and wasn't worried about it. I've had a pimple on my penis before, so I figured it was just that. I actually popped it and there is a small scar where it used to be. 

Now there are a couple around my shaft scattered throughout - they don't hurt, itch, and I don't feel them at all. Today I noticed two of them right next to each other and they look like two tiny pimples. I haven't had unprotected sex in over 3 months and they kind of just appeared, so I'm concerned.