I would say chewing stage. It also sounds like it is due to boredom. You're sleeping and she's not. I would try giving her the frozen washclothes, harder toys, and some lare raw bones to gnaw on. A good bone, with a little bit of meat or gristle left on it, will occupy my guys for literally 2 - 3 hours. Trying to get that little bit of whatever smells and tastes so good, is utterly engrossing for them. Femur bones are good, pork shoulder bones, shank bones, etc. Something that is big enough to hold with their paws, so they are physically biting and tugging on it, is great exercise as well as entertaining. Good luck.
Kathy