Mouse suddenly goes crazy?

Question
What could be wronge with our mouse out of the clear blue she just attacked two of our mice and shes acking funny normally shes calm now she is frantically moving? And as i held her she bit me...

Answer
Hi Jessica,

I need a little more information to help you find what is going on.  It definitely sounds like something is bothering her!  For the time being it may be best to separate her from the others, place her enclosure in a quiet part of the house away from drafts, noises, and high traffic, and give her a few days to calm down.

Some questions that might help narrow it down:

-How long have you had her and each of her cagemates?  Do you know how old each one is?
-Has anything changed recently - a new diet, new toys, a different bedding, a new person in the house?
-How does she look healthwise - are her eyes bright and clear?  Is she responsive, sleeping during the day, and awake and active at night?  Is she moving normally?  Are there any scabs/missing spots of fur on her coat?  Are her ears, feet, and tail all normal and healthy?
-Has she been drinking and eating well?  Are her stools normal?

It's important to examine her environment closely, as well as her physical appearance and behavior.  If you can find any clues, write me back with as many details as you can and I'll see if I can help you figure it out.

Best of luck!
-Tam