1: A signal used when someone is pissed to the point of not caring anymore. Usually means you broke 'em bro. Often a sarcastic reply to excessive amounts of complaining. More specifically a sarcastic reply to some dumbass getting upset if you make a "mistake".
2: said when a genuine mistake is made.
3: said when a mistake was made on purpose.
1: idiot: I hate math
Me: oof
Idiot: I hate ice cream
Me: damn
Idiot: I'm booooored
Me: sorry?
Idiot: you're no fun
Me: whoops.
2: me *knocks over Coke and spills on friend accidentally* whoops!
3: me: *knocks Coke over and spills on crush so I have an excuse to fluster and grab some napkins for him, opening up possible conversation- even tho I'm too awkward to actually do that but whatever idfc* whoops.