A man went to his doctor and said: "Doctor, I've got a problem, but if you're going to treat it, first you have to promise not to laugh."
"Of course I won't laugh," the doctor said. "I'm a professional. In over 20 years, I've never laughed at a patient."
"Ok then," the man said as he proceeded to drop his trousers, revealing the tiniest penis the doctor had ever seen. Unable to control himself, the doctor fell laughing to the floor.
When he was able to regain composure, he said, "I'm so very sorry. I don't know what came over me. On my honor as a doctor and a gentleman, I promise it won't happen again. Now what seems to be the problem?"
"It's swollen."