
Sorry to hear your girl isn't acting herself. Try posting over on the ER forum with all the details (a photo might help too), hopefully someone over there can help you out. In the meantime, it's good you separated her...see if you can get her to eat some scrambled egg and drink some water with electrolytes in it. She needs to stay hydrated and take in some nourishment.
https://www.backyardchickens.com/f/10/emergencies-diseases-injuries-and-cures
Best of luck to you and your girl.