I think that you will have to leave him for quite a while before you go looking again. Hopefully the temps are cool enough to allow for this. Blood on the ground can be really desceaving as to really how much he lost. Looks like a lot, but might not be so much. That should be a killing shot in my opinion, but it might take a while. I shot a doe as you did..waited 1 1/2 hours before I started tracking her and kicked her up once. I backed out and came back 4 hours later and then found her. Time can only help you. Good luck and keep us posted.