Proof that my Brain is slowly turning to Mush

The scene:
The office where I work. It is lunch time and the door is locked. I am sitting at my desk in front of the window eating my lunch(alone. sniff).

A woman comes to the door and tries to open it, but finds that it is locked.
I say to her "We're closed for lunch".
She says loudly, through the glass door
"I just need to pick up some rubber bands"
I walk over the drawer where we keep the office supplies and pull out a package of rubber bands from the drawer. "How many do you need?" I ask.
She starts laughing. "Oh, I meant for my daughter's teeth."
(Smacks self in forehead) Did I mention I work for an orthodontist?

Somebody please help me. There must be something I can take for this. If it is true that you lose your mind after you have kids, I am in so much trouble.