In the heat of the moment do you really think the average street cop knows, or can remember, the sequence of shots? Once the adrenaline is gone so is the memory most of the time.
In the Andy Lopez shooting report out there in Santa Rosa the ME and Ballistics were able to determine which shots and which bullet holes came in which order and thus reproduce the crime scene.
So the officer here can relax if his memory is not that good.
He will have forensic help.