The literal opposite to 'green day' it has nothing to do with weed. A 'red night' is when you go out into the streets with a best friend and throw everything out the window and don't care about the after affects. You go nuts and party, smash things up, shag some random person, do a pound of cocaine, blow up a car, etc. It's a last resort to have fun before you explode. Imagine a rave at a punk-rock club going haywire and everyone there on everything imaginable freaks out. Half the time its not regrettable, though, and music is a big role in it.
Usually you end up dead, in jail, or hurtin pretty bad.
"Dude, Bobby got mobbed by some gang last night..."
"I heard it was just another punk 'red night' for thies kids on blah blah street."
"What happened last night? I was wondering where you were- look at you! You're all beat up!"
"Ah, it was another red night, I guess. I'm ok, i promise."