what happen to you when you get knocked out from a punch in the face?

Answer 1

Uh....it hurts, you may get a broken nose, a black eye, you go unconscious and may get a concussion. Who knows, depends on how hard you are hit and where on the face. Hope you don't plan on doing this to someone.

Answer 2

With luck you come to in a few seconds/minutes with a hell of a headache and no worse for wear! There can be real serious harm if it happens to many times. Such is the case with many pro boxers!