Intent in courts is a funny thing. If you shoot the bad guy in the stomach and the threat stops and in court you say "Well I didn't want to kill him so my intent was to injure him until he stopped." But it turned out your shot hit him in the spine. So it gets all spun around until they're trying to say it was your intent to shoot his spine, put him in a wheelchair and ruin the rest of his now disabled life.
So no matter what is going on in your brain, when your mouth opens you "Shoot because you were fearful of your life." If you end up with headshots, twelve in the chest, or just one in the buttocks, you shot because you thought he was going to hurt or kill you. Other than that, you shouldn't say much.
Hopefully it won't even go to trial, and if it does, you don't have to speak, your lawyer can present your case. You were frightened, you believed he was going to harm you/others, so you fired your weapon at him until you felt safe.
If someone shoots a badguy 15 times, oh well he was a bad guy. As long as the evidence doesn't shot you shot him, stood over him, and shot him 12 more times, then whatever. I do recommend keeping a few in the mag in case of a bad friend nearby!
This whole discussion reminds me of Albert Camus' The Stranger. A novella where at one point a character shoots another man after he was cut by a knife. The man dies and then the Stranger shoots him 4 more times. At trial there is a huge deal made about the 1 + 4 shots meaning he is a horrible and unrepentant person as the first shot was at least somewhat understandable, but the other 4, fired after delay, make him a criminal. A pretty good book and that's not the end, so it hasn't been spoiled for you.