Do you have skin problems anywhere else on your body? It looks more like a skin problem, but you need to rule out the possibility that it is something that has been in contact with your penile skin.
When did this first show?
Check whether you have changed soaps or shower gel or any other body wash recently?
Are you sexually active and / or use Lubes for masturbation, that kind of thing?
If you want to arrange an appointment try to get to see a Dermatologist