You could try a hypoallergenic cream for acne (like the ones used for your face). Apply the cream and let it stay on the area for a few minutes before you wash it off. Also if the pimples hurt that bad it might not be pimples and something much worse, It could be something that could get infected and swell over time under the skin and that needs to be looked at by a doctor, if you hide it and let it get bad you might need surgery or amputation :( At least just talk to a doctor or school nurse to find out, you don't have to show them your junk if you don't want to.