My crestie decided to jump off my arm today and fell about 4ft. onto solid ground. There was a loud noise when he hit. Don't know how much he weighs, but he's about 3-4" long from snout to the end of his tail. At first he just lied there, but after I picked him up he continued to hop around. Should I be worried that it might be hurt? Are there any signs of serious injury I should look for or was it probably just scared.