Just recently I have been getting bumps the size of mosquito bits all over my shoulders and arms they itch and some are next to each other and others are in a row there are about 8 bumps on my right shoulder and 3 bumps on my left shoulder then later on in the day it spread to my hands now there is a bump on each hand there is also 4 bumps on my upper right arm what is it and how do i stop it?