I have two girls, Misha and Mini, and I just noticed that Misha is walking oddly with her back hunched and is standing on her back toes? She is a very hyper rat that is not used to being handled yet, but she just stood still while I picked her up and is very calm. Mini is fine, but Misha's fur is poofy and messed up. I gave Misha a treat and she ate it. She was acting fine last night, what is happening? Please help a.s.a.p! ???