My point is that kids have been primed, through many sources, to NOT chill when cops are talking with them. It's like being given PTSD for something they've never experienced themselves.
Kids watch a hundred bodycam videos of cops shooting people before ever actually interacting with one, and they just assume the cop's job is to talk for a while and then slam people on the ground or start shooting. So that's what she's subconsciously expecting next.
Is it a reasonable fear? Probably not. But the guy does have reinforcements and he's getting increasingly irritated as she gets increasingly nervous. He's just trying to get her info and be on his way, and she's preparing to go to jail or die.