I had a hen that hurt her leg and when I found her was also a but shell-shocked. It appears the others that she was with started attacking her (they perceived her as a weak link and fodder for predators and wanted her gone I guess). I separated her out into a puppy ex-pen (a few feet in diameter) in a horse stall with one other (badly molting) hen that was not in the pen for company, but she pretty much laid down and didn't move for the first week or so. I kept food and water right by her "spot" and hoped for then best. It took a good month for her to be able to walk normally again. I believe that increasing her protein helped her rehabilitate. I have her "feather fixer" (high protein pellets) scrambled egg and even canned sardines. Since she wasn't able to forage, when. She improved I tossed in some mealworms, sunflower seed (hulled) and gave her fresh greens. Maybe if I had limited her movement more she would have healed faster (?). My gut told me to let her move freely when she felt like it to keep her muscles toned. If your chick is separate and feels secure in his/her surroundings, it may not further injure itself. Good luck with your baby! It's amazing how much we do for our chickens.