My little Annie B had bad dreams after I first rescued her. She was a breeder at a puppy mill. They got fewer and farther apart as time went on. But her's were never as serious sounding as these.
I hesitate to say, but could these actually be some type of seizure? The not waking up easily is a red flag to me. I would encourage you to discuss this with your vet and see if there is anything that can be tested for. I hope I'm wrong, but I feel I needed to point this possibility out.
Keep us informed about what's going on and please post pictures of your "kids" when you can.
