Sounds like you hit just under the spine where there really is nothing.
Lets look at it this way? If you had hit the spine and penterated it he would have droped right there? So thats out! Sounds like your arrow hit way to high to hit any vital`s hart, lung,liver, ect... so thats out! Now you say your arrow did not penitrat much at all (imo) He`s fine. Sore yes! but still running around out there and most likely will be for a long time to come. just my 2 cents worth..
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