Wiktionary
bag of nerves
n. (context informal English) A very nervous person.
Usage examples of "bag of nerves".
Maddy, who of all people he thought should be used to the camera, was a bag of nerves too, enough even to seem oblivious to Steff's feeling like a shambling amateur.
He's the worst agent material I've ever set eyes on: idealistic, unstable and a bag of nerves.