Hi all I have recently bought my 2 rhode island reds and 3 orpingtons. They are 6 weeks old.Its the first time I am owning and raising chickens. 1 rhode island red doesnt look well at all. She closed her eyes and pick her head up and down, at the same time open and closes her mouth. She is definitely not ad active and bubbly as the rest. What should I do?