What Causes Red Spots On The Head Of The Penis?

I just had intercourse with my girlfriend. Right after sex we went to go shower and I noticed these dark red spots all over the head of my penis. My girlfriend did give me oral sex for a long time tonight. Are these spots burst capillaries or something? I have never had an STD. The spots don't hurt or itch but are still there but not as dark now. What is this?