I'm so sorry for you! Poor little Tia.
Is she licking her leg or any part of her back end? How is Bailey acting towards her? Is he sniffing any her leg or back? Try putting her down and walking a few steps away and calling her or offering her a favorite treat. Then you could see if she's limping.
Please keep us posted on her condition. Prayers coming your way.
Also remember to keep her warm and watch for hypoglycemia since stress can cause this. Is she peeing normally?