It sounds like keratosis pilaris. It's little red and white bumps on the upper arm but it can also spread to the forearm and legs.  It doesn't itch or anything but it's not very attractive.  I had it all my life until I found this great stuff at Sephora called KP Duty by Derma Doctor.  It's a little expensive but it really works.  You need to get both the exfoliator and the lotion.  Separately they work for a while but it comes right back.  Together it stays gone.  I went to the dermatologist and he prescribed something but it didn't work.  The only problem I have now is scarring (from scratching the bumps and such) since I had it for so long but if its recent to you that probably won't be a problem.  Hope this helps.