22 week old chicken has been laying for about a week. This morning she had a rubber egg, is drinking a lot. Her vent is clean but some of the lower feathers and very tip of her tail feathers are a little damp. She was fine yesterday... None of the other chickens are acting like this. I am a new backyard chicken owner. I fed her some yogurt and added ACV to the water. Is there anything else I should do?