be falling over yourself to do something
be falling over (oneself) to (do something)
To do something in a way that reveals one's overeagerness. The phrase is typically used to depict such behavior as foolish or pathetic. Oh, he's been falling over himself to impress some girl in his class.
be falling over yourself to do somethingINFORMAL
If people are falling over themselves to do something, they are very enthusiastic about doing it. Within days of his death his former friends were falling over themselves to denounce him. Hollywood producers were falling over themselves to put me on the silver screen. Note: This expression is often used to show disapproval.