Sorry about your pullet. Is her neck stuck down, or is it limp—can you raise it? Is she walking okay, or is she imbalanced? Could she have been kept from food and water by the others, since she was acting off? Can she drink some water for you? I would give electrolytes and vitamins if possible. Vitamin E would be good. It does appear to be wry neck (torticolis) but the drooping wings might be a sign of dehydration or even Mareks disease. What do the poops look like? Try to separate her in a dog crate for observation. Get her eating and drinking, and some like chick feed mixed with water in a small bow and scrambled bits of egg.