You're in a store looking at items minding your own business and out of nowhere a guy screams out and points that you it was him/her how do you react what's your next move

Okay. Listen here, sir. I don't know who you are, and you're probably insane, so I'm gonna call an ambulance, get you taken straight to a mental hospital, and come back when you actually are right in the head, because currently, you make no sense. Also, I wasn't- I don't even know who you are, and also, I'm pretty sure you're hallucinating, because I don't even exist. And then, like, I run away.