it's too bad you didn't see where you hit him at, that would help out a lot. from the way he's acting (walking kind've slow) it sounds like you may have hit some liver or stomach. was he hunched up at all with his head down? was he limping off any leg? could you tell what color the blood was, dark or light/bright color? do you think you jumped him as you neared the willows? chances are if you got into the body cavity, whether it's guts or liver, he's dead in the willows. if the frost wasn't a factor i'd let him go till morning. since it is i'd go out around 10 or 11 tonight and find him. what time did you shoot him about?