After many years of hunting and watching arrow hit deer both good and not so good shots and like you learned my lesson the hard way this is my current routine.
When I shoot a deer, unless I see him fall, whether I think it's a good shot or not I go to my truck and have a cup of coffee and stew for about an hour or so. That's if I think its a good shot. If the shot is iffy, I'll go have breakfast and wait at least 2-4 hours. If he's dead, he won't get any deader.
This has worked for me and I haven't lost any of my last 15 or so deer.