Nurses aren't supposed to laugh...

'Of course I won't laugh, said the nurse. I'm a professional.
In over twenty years I've never laughed at a patient.'

'Okay then, said Fred, and he proceeded to drop his trousers, revealing the tiniest 'man thingy' the nurse had ever seen. Length and width, it couldn't have been bigger than  a AAA battery. Unable to control herself, the nurse started giggling, then fell to the floor laughing.

Ten minutes later she was able to struggle to her feet and regain her composure.

'I am so sorry,' she said. 'I don't know what came over me. On my honour as a nurse and a lady, I promise it won't happen again. Now, tell me, what seems to be the problem?'

...'It's swollen,' Fred replied.

She ran out of the room.