In my personal opinion, when an animal "needs to be put down" it is for the animal, not the animals owner. I have had the experience more than once, and it's never easy. I made a BIG mistake with one. I wanted to enjoy, as best as possible, the last several days, while at the same time my dog was not having any real peace, enjoyment, free of pain perhaps, and seriously needed to be put down. It was a weekend, and then Monday a holiday, and the vet would be closed. I had to shot my dog in the head, more than once, and it does not get any worse then that. Never wait too late and be selfish by not given your pet the needed peace they deserve. The dog may have died with the first shot, but all it took was a twitch to make me shot fast and wildly hoping it would be over sooner. Broke my heart and I cried right there.