i didnt want to say anything before reading the other posts to see if you got him but...my buddy hit a deer with similar blood trail...it looked like everytime the deer exhalled it sprayed blood everywhere, that same bright red watery blood and we tracked and tracked for hours on our hands and knees and the trail stopped...i believe that was a flesh wound...your deer probably clotted up before it could have bled to death....I'm no expert by any means so Id keep looking but if he made it through the night and ran from you, id say he's ok