Suggest Treatment For Itching And Red Spot On Penis

Dear Doc., I am ko ko and suffering from itchiness in penis for a couple of week ago and I found one red spot on black scar and very itchy. Please help. My age is 46 and body weight is 185 lbs. I slept with my girlfreind before that and she also complain about itchness and by now she does'nt complain anymore.