I just noticed today that my 4 week old Welsummer chick was acting quite strangely. He always just wants to lie down and sleep, but when he's standing, he has his neck scrunched up into his body and walks like his legs are too heavy. He kind of brings them around the side more than just straight forward when walking. I also noticed that he was breathing kind of heavily. His body seemed to be moving more drastically with each breath when compared to the others. He has been eating and drinking and I haven't noticed any other symptoms. Does anyone have any ideas as to what is ailing my chick?