I'm 19 and just noticed them, maybe I've never looked close enough, but now that I see them I wonder how I couldn't have noticed them. When I retract my foreskin and look closely I see a cluster of small white bumps. They kind of go around the underside and sides of my penis like a ring but not on the top. I'm sure they're not sebaceous glands. I also have PPP. I'll take a picture later.
They look like the bumps at the very bottom of that cluster.