this really resembles a yeast infection. have you had an unprotected encounter? clotrimazole can be used to treat thrush on the penis. is it just red is there also some ulceration?
Has this occurred following sexual activity? When did this first appear? If this is not sexually linked you may have a skin condition developing … if the symptoms worsen greatly, then either see a Doctor, or if you can, see a Dermatologist …