One of those unpleasant experiences happened just this bow season. I shot a doe at about 25 yds, high in the back due to my height in the tree. She made this high pitched bleat and tried to run, but fell right over on top of the arrow, snapping it off. For an eternity it seemed, she kept raising her head and bleating and kicking her feet trying to get up, but she just couldn't. I think it lasted a couple of minutes. I do know that as each second went by, I felt worse. That first bleat though, got me more than the rest. The other deer all watching from 30-40yds away. You know, I have found deer in many positions on the recovery. I once had a doe that I hit as perfect as you can with pass through hit. She still went 100 yds on wobbly legs, and laid down like she was posing for a nativity scene. Like she was sleeping. That kind of stuff makes you always want to get the cleanest quickest kill possible. Even perfect shots sometimes don't work as quick as they should. Just be happy you feel something. Many don't.
I still feel a bit of remorse with every deer I kill. I love animals. If I am not hunting deer, I want deer to live.