Killing rabbits

[Ivanator]

So today I went to the store to get a rabbit for my big retic and I asked them to kill it for me. When I got home and opened the bag they put it in, to my surprise, it was still alive but it couldn't move except for blinking and, just my luck, my snake decided he didn't want to eat today, he was in shed but he usually still eats, so I didn't know what to do with the rabbit because I don't wanna freeze it while its still alive. I put it in a container and to my surprise again, it suddenly lifted its head up and looked around then laid back down so I decided I'd give it the day and maybe it'll regain control of everything else. Well I just got home and its still just lying there. Alive and pooing. What should I do? I have no problem killing rats but for some reason, rabbits are just too hard to kill for me. They don't look weird or bite or smell like rats so they're harder.