Nick Young -- Cops Want A Piece of Swaggy P (VIDEO)

Nick Young seems to be taking aim at the LAPD ... except we think he's joking, and he's drunk.

Our photog got the Lakers star Friday night outside the Nice Guy in L.A. Friday night ... and he's clearly feeling no pain.

Nick is all about the men in blue ... scoffing at the importance of that knife on OJ's property, and questioning cops who busted him for bumping loud music in a rental car.