“The teen picked up the gun that he dropped and limped out of the store.”
___
The 61-yr-old shouldn’t have allowed that. A couple more shots and he wouldn’t have to always be looking over his shoulder for the 16-yr-old punk to get his revenge.
[“The teen picked up the gun that he dropped and limped out of the store.”]
Given that the potential victim has the advantage here, don’t let them leave with the evidence if possible. He might have attacked some other person outside just before (whatever) - dying, being driven off, etc.
Lock the door and assume a defensive position until the police arrive and stay in contact with them if you can.
At least, that’s what I would do.
Should have shot the perp again as he reached for his gun, not just watched.