I have a female mouse that keeps running in counter-clockwise circles: sometimes around the edge of the cage, sometimes in tight circles like she is chasing her tail. She is housed with another female. They get along fine. I have had them for about 2-3 months, so I am fairly new to keeping mice. There are two wheels in the cage, which the other female frequents. The other female doesn't run in circles that I have seen. Is this normal? Is she possibly burning off excess energy? Could it be neurological?
Any input will be greatly appreciated.

