What Is The Cause Of Red Bumps And Itching Of Skin?

i just got sprayed with diesel yesterday and drove home with my shirt soaked, by the time i got home it was burning and itching and i took my shirt off and i had red bumps all over in my arm, right where the elbow is on the sensitive skin on the inside and on my forearms and it has gotten worse since then. it is still burning and i was wondering what is the best way to get rid of it?