Hi , I have gone through your question and understand your concerns. Its likely that you are suffering from folliculitis. Folliculitis is the infection and inflammation of one or more hair follicles. The condition may occur anywhere on the skin with the exception of the palms of the hands and soles of the feet. The rash may appear as pimple with underlying pus collection. As pubic area is highly rich in hair follicles and More prone area of having infections. I suggest you should keep clean your pubic area and consult your physician as you may need antibiotics like co-amoxiclav to clear up the infection. Hope I have answered your question. If you have any other query please feel free to ask. Wish you good health.