Nu, a daygeh? from Cabaret Warsaw
Peysach Burstein sang this song first - he called himself, among other things, a "coupletist" - meaning he sang comical songs with extemporized rhyming verses. Sometimes couplets were topical, about issues of the time (like a Jay Leno monologue, maybe).
It's hard to translate this refrain. I used several different possibilities in the captions. Maybe Alfred E. Neuman's "What, me worry?" would be best.