If it makes you feel a little better , I know that fear that you are going through. A few weeks ago Gucci my puppy lost her footing on my couch and took a 3ft drop on to my ceramic tiles. I heard a thump from upstairs and ran downstairs she was motionless and her body was stiff. I thought she died. Make a long story short , I rushed her to the vet, he said she knocked the wind out of herself. I had to give her anti imflatatory pills for a week.
I had to watch her for a few days, she bounced right back so Im sure Hunter will be fine.. Just keep an eye out on him...Good Luck