Hi look the doctor over looked some thing, as I have just been working with some body try this as an answer, if you have been wearing condome lately you could have become latex allergic, as your syptoms match the same as latex allergies.
Just google latex allergies and read on an see if they match.
Good Luck
Hello and welcome!
It is difficult to confirm anything without an external examination. This could be eczema, dermatitis, bacterial or fungal skin infection .The diagnosis for penis skin rash is done through the examining the symptoms. There are good treatments available for the penis skin rash based on the accurate diagnosis. Medication is preferred as the topical creams or ointments may cause irritation and pain. You may apply moisturizers to the skin of penis to reduce the dryness. Seek medical opinion and keep us posted.
Take care and regards!