I've had them as far as I can remember back. I have them on my forearms and upper arms. They are tiny, pinprick sized red dots placed at random intervals under my skin. There aren't a lot of them, though.
But when you kinda 'scrape' at it, it will go away for few seconds, and then fade back into view.
I don't think it's much of anything at all, but I just want to know.
What causes this, anyways?