Stay and address the police when they show up.
Yes, you will need to have alternative firearms available - you may not see that weapon again for months, years or ever.
You don’t want to leave an unattended corpse laying around. If you leave the scene it will certainly add to your police issues.
Call your lawyer immediately. Say as little as possible until the lawyer shows up to advise you.
DO NOT YELL ‘Have a nice day’, to the fleeing individuals. That was a joke, son.
DO NOT YELL ‘Have a nice day’
No, it’s much funnier to yell: “Y’all come back now, ya hear?”