help please

[mamajudes]

I went to my coop just now to check on my chickens and give them some grapes and meal worms. One of my girls (Sapphire gem) is laying on her chest with her feet sprawled behind her. She was fine yesterday afternoon; even layed an egg.....The other two seem fine. I picked her up and looked at her; didn't see anything that looks injured. She has always been friendly and healthy; all of them have been. I put her near some food and she ate readily. She tried to get up but when she tried to take a step, she feel forward again. I didn't know if she felt cold (it snowed all night and is cold but they have a coop with a door that leads to the run; none of the chickens have been out at all) . I thought maybe she was too cold, so I put up a flat panel warmer near her; won't leave it on if this isn't good. She has some poop on her butt area but not plugged up with poop or anything.
Can anyone help me? I don't know what to do; this is our first winter with chickens; just got them in March. They have been totally healthy always. Very social with me, and everything has went smooth until today.

 

[Eggcessive]

How old is the chicken? Did you get her as a baby chick, and was she vaccinated for Mareks disease? Pictures of how she is lying would be helpful. Can you see any swelling or color change in her feet? I worry a bit about possible Mareks disease, but frostbite could also be a problem. Are their ant roosters who might have injured her back or legs? She may need to be fed several times a day if she is unable to reach food and water. I usually mix a small cup of chicken feed made very wet with water, add some scrambled chopped egg or tuna, and try to get them to eat several times a day.

 

[mamajudes]

We got her as a baby chick last March. She was not vaccinated. No roosters.
She managed to get into a nesting box and laid an egg. Her legs are still behind her even in the nesting box. I am concerned. I will try to take a picture of how she lays with feet and legs behind her. I keep our coop clean and they have nesting bedding to help with warmth. I don't see any difference in her feet; not sure what it would look like if frostbite.
Should I do anything else?