When you see all of that blood you want to go after him right away, BUT you really need to wait and let the shot do its job. My biggest deer bleed alot at first and after 30 yards or so it slowed way down. I stopped and waited over an hour and he only went 50 more yards, he laid down and never got up. I think that you might have been jumping him up and that is why he went so far. I hope you try again and find your buck, good luck.