A lot of pet stores (both local and the big chains) can be pretty ignorant when it comes to animals, especially reptiles and anything to do with them. It sounds like she was just being a sarcastic b- I mean witch I have never heard of mice having a "heart attack" before. The only way it might have is if your snake actually struck at it or bit and released and it was an old mouse or a mouse with a health problem and it couldn't handle it. Either way it sounds like it was the pet store's fault (indirectly) for selling "defective" mice. Unfortunately there's probably not much you can do about it. You have to go with what you get.

Quote Originally Posted by cinderbird View Post
I don't know what to tell you about the mice, but trying to feed your snake multiple times in a short time period will only make it refuse further. If your snake refuses, wait a week(7 days) and try again. If you feed live, unfortunately you have to keep the mice around for a while.
I definitely second this. I know it's tempting to try and feed again right away, but it really can cause them to refuse food and get more stressed. Wait at least a few days, but a week would probably be best. And yup, it can be a pain keeping the live mice around for that long but...you gotta do what ya gotta do