ORIGINAL: GregH
I had a hit just like that, in the shoulder blade. It is possible for the blood to come out of the wound and cover the arrow to make it look like more penetration than what you really had. There were a few tiny bubbles in my blood trail also. Maybe caused by mixing with water on the leaves?? After 80 yards of profuse bleeding the trail completely stopped. The deer lived. These are called muscle hits.
I am hoping thats what happened. The only bad thing is that if he does live his opposite side antler will probably be messed up from next year on[&:]