No blood? Sometimes with a high hit you won't get much blood on the ground for several yards. Don't push him! Give it till morning. If you got one lung it most likley is fatal but not unheard of to go couple hundred yards. If you find blood it should be brite red and full of bubbles if it's a lung hit. Bubbles will be gone by morning and blood a little darker. Real dark and foul smelling is a gut hit but if it was quartering away and just behind the shoulder he's hit in the lung(s). Read the after the shot in Bowhunting forum if you haven't done so yet. Get ready for the longest sleepless night of your life. I had to back out once overnight but found him withing 75 yards of where I shot. Good luck and don't give up till you find him or are 101 percent sure it's a clean miss. Like I said, Dont push and he won't go far.