Every pet owner has experienced the sheer panic that arises when your fur baby starts to display strange behavior, like refusing to go outside or hiding under the bed.
You think Fido is dying because he's been hiding in the closet all week and won't eat, so you race him to the vet, panic in the waiting room for an hour, and then Fido gets up, sniffs some other dog's balls, barks at a cat, and the vet is like, "I dunno your dog seems extremely normal, maybe he was in a mood?" And then you give the vet $500 for nothing and sulk home, cursing at Fido, who is now chilling in the backseat with his head out the window.