Consider it a practice drill in 2 respects:
1. Carrry Carry Carry - next time it could be real
2. Know that if you ever think it's real, use utmost caution in firing - it could be a prank.
The best example from my CCW class was a real case where a cop busted in and saw bloody man on top of woman. Looked like man was strangling woman. Cop shoots man in back, killing him.
Turns out that the 911 was called by the man. The woman was the perp. and was stabbing the husband in the chest. He rolled over on top of her, trying to get the knife away from her.
Basically, cop shot the victim (or rather, finished off what the lady perp started).
This is why, I think the best CCW practice is the use of role-playing as part of video-based scenario (you shoot at a big piece of paper which has the video image displayed on it). It will make you really adept in the real-life type of thing you encountered.