Hi! What does it look like? are the bumps white? or do they look like blisters?
It could be warts OR herpes OR a dermatitis which is not and std but and allergy to soaps, foods, etc.........
see your doctor and please and "make sure" that the doc test you because some don't!!
and you can't tell just by looking!!!! even if your doc says he/she can.
take care!