Have you tried to feed her a rat that's the same size as her widest part? She might just be really hungry and the mice might not be filling her up for very long. It's a thought. Also if she's that stressed then you might just want to leave her alone for a week or two. She's a baby so handling her might be scaring her. Also babies are nippy. We are giants to them. As a defense mechanism to keep from being eaten they bite. Heck if a giant tried to manhandle me I would bite too.