My Foot Hurts, Feet Hurt

One evening about 24 years ago, my husband came up from behind me and whispered (into my bad ear), "My feet hurt."
I said, "Aww, what happened?"
He said, smiling, "You happened."
I said, "What?! What did I do to make your feet hurt?"
He said, "My feet don't hurt."
I said, "Yes, they do."
He said, "No, they don't."
I said, "Why did you just tell me your feet hurt?"
He said, "You're cookoo. I never said that."
I said, "Yes, you did, you came up to me and whispered 'my feet hurt'."
He said, "I said, 'my sweetheart', I was whispering sweet nothings into your ear."
I said, "That was my bad ear and who are you calling cookoo?"
So, the joke has been for 24 years that we call each other "feet hurt."
Today I said, "My foot hurts."
He said, "You mean feet hurt."
I said, "No, my foot hurts. I dropped the toilet tank top on it and I think I need stitches."
He said, "You're cookoo."
I said, "Please take me to the hospital."
He said, "How bad does your foot hurt, feet hurt?"
I said, "Bad and who are you calling cookoo?"