I did the same thing on a monster buck this year hunting in Oklahoma. I was a far shot 45 yards and the buck dropped in his tracks. He stayed down three minutes and then walked in the woods. I lost is blood trail, used dogs and never found him. I'm sure I hit him high. I didn't get a pass through the arrow broke when he dropped but blood was dripping on both sides. I just hope I pierced him and he didn't die.
I'm real confident of my shooting, but I think I misjudged the distance a little.
I should have sent another arrow, but I after seeing him drop instantly I thought I nailed him.
That's bow hunting.