This could indeed be be due to irritation, infection or other skin
condition such as dermatitis. The skin
of the glans is very sensitive and can be easily damaged, which may lead to infection. Irritation of the skin can be caused by the soap you are using, over-washing or scrubbing, chemicals in some condoms, spermicides, and lubricants,
or some washing powders or fabric conditioners that are not completely rinsed from the underwear. Try to use mild soap and detergents.