"I Am Holding My Brain." joke

A lady named Linda went to Arkansas last week to visit her in-laws, and while there, went to a store.
She parked next to a car with a woman sitting in it, her eyes closed and hands behind her head,
apparently sleeping. When Linda came out a while later, she again saw the woman, her hands still
behind her head but with her eyes open. The woman looked very strange, so Linda tapped on the window
and said "Are you okay?"
The woman answered "I've been shot in the head, and I am holding my brains in."
Linda didn't know what to do, so she ran into the store, where store officials called the paramedics.
They had to break into the car because the door was locked. When they got in, they found that the
woman had bread dough on the back of her head and in her hands.
A Pilsbury biscuit canister had exploded, apparently from the heat in the car, making a loud
explosion like that of a gunshot, and hit her in the head. When she reached back to find what it was,
she felt the dough and thought it was her brains. She passed out from fright at first, then attempted
to hold her brains in.