Is my brain leaking?

When we were walking today I said to husband, 'I'm seriously thinking of going to the doctor's about my permanently runny nose.'

'You're not going to tell him you think your brain is leaking, are you?'

'Well, he might not have seen that episode of Grey's Anatomy; he might not know it's a possibility.'

I have little enough brain as it is; I really don't need to lose any more.