Guess he's living up to his name jk

Don't feel insulted. ALL snakes have the potential to go all crazy and "wild" right after they've been fed, no matter how sweet and laid back they are the rest of the time. Food brings out the primal instincts in all animals, and when they're in "feeding mode" and are still hungry they will snap at anything that moves. I've had all of my normally docile snakes go after me at least once when I was trying to transfer them back into their enclosures from their feeding container, and that's the main reason why I decided to stop transferring them back and forth and just feed them in their enclosures. I haven't had a problem since.

I understand the potential hazards of feeding a KSB in its enclosure though, so my suggestion would be to just let him slither out on his own next time unless you feel comfortable picking him up, and then maybe wear a gardening glove just in case. It's pretty common behavior for most snakes