My rat, Spice, has been extremely lazy for the past couple of days. She wont go out of the cage unless I pick her up and move her there. She is not over weight. I also have checked her ears, eyes, and nose for signs of sickness. I even listened to her breathing and everything was normal. She has always been a very calm and sweet rat. I am concerned mostly, because she is a female rat and she used to always go out of the cage. She is only 9 months old. Is she sick? or is she just an extremely lazy rat?