It's impossible to diagnose anything over the internet and, as non-vets, something we shouldn't do anyway. My only suggestions would be to limit his ability to climb and possibly hurt himself and then get him to a vet. Keep him plenty warm. I know the panic you feel. Loofah took a flying leap out of her enclosure the other day onto the cement floor. After she hit she held her back leg up and shook it a bit and I was sure she had broken it. After a few minutes she was fine and back running around. Please keep us informed.