About a week ago, our Jack Russell got a hold of one of our chickens, she's only 3 months old. We couldn't find any puncture wounds or any outside damage. She seemed fine for a few days, except she was afraid to come out of her house. Now she can't stand. When I pick her up from behind her right side under her wing is swollen, feels like a balloon, full of air. She will eat and drink and will flap her wings and scoot around, but not alot. This is our first time with chickens and I don't know what to do.