What was the epiphany at the end?
****** SPOILERS AHEAD ******
So at the end, she shoots the 2 guys, takes the money, starts walking towards the door, and we hear police park on the other side of the door. Then she stops and turns around and has a realization.
So, my guess is those two guys surviving before she shoots them are cops, and since one of them got to the phone, he's the only one called for the backup of other guys and that's the reason why the police show up in the first place. The second guy says, let's go on a beer, and that the feds are going to be there within 15 minutes. How did he know this unless he knew other guy is the police officer as well and concluded that the other guy called for the backup?
This is what she realizes towards the end since only the police guy would call the feds for the backup. And that she's fucked.
Am I missing something here?