Got an almost 1 day old chick and it is mainly sitting on its bum. Haven't had many chicks so this is new to us. Our chickens are bantams. Hen had 8 chicks and this one is a little different. Took it inside and put in a box wrapped up in an old woollen sock as not got a proper heating lamp, using a normal lamp instead and got box sitting on a hot water bottle to keep it warm. It is drinking and eating a little, but keeps falling back on its bum when walking. Should I be concerned and what can I do?