Nova loves walking around the house. She'll scratch and scratch at her tank until we let her out and set her down and she's off to the races. She'll tear through the hall, the living room and all the way into the kitchen. It's a daily thing, sometimes more than once a day. And it makes her super bright orange BUT her beard and last part of her tail get super dark, real black. I don't think she gets streaked, but those other things do happen and I can't figure out why. She likes running around but gets stressed.? What does that mean, is she even getting stressed.?