I have a rash with small white pimple-like bumps. Is it serious?

A few days ago I started grappling with a friend who is in amatuer MMA. Yesterday I noticed a rash with pimple like bumps on my arm and knees. I am afraid it might be a staph infection but I did some research online and most serious staff infections are bigger than a pimple, more like a boil. Do I have anything to worry about?