A husband rolls over in bed, wiggles his eyebrows suggestively and gives his wife a wink.
“Oh not tonight,” she says. “I have a headache.”
The next night, the husband tries the same move, but is rebuffed again.
On the third night, the husband walks into the bedroom holding two painkillers and a glass of water.
His wife asks, “What’s that for?”
“It’s for your headache,” he replies.
“I don’t have a headache.”
The husband smiles and says, “Gotcha!”