My suggestions is to get her another hide and cover up 3 sides of her tank with black paper in order to give her a better feeling of security if it is stress. If not it still couldn't hurt anything.

It could also be because she is still hungry after her weekly feedings. Hopper mice are called so because they are weaned and hop around, does that sound like the prey you are using?
Anyway I would recommend either increasing the size of her prey (not bigger than slightly bigger than her biggest girth) or offering her another after her first mouse on feeding days.