I would suggest you have your dog checked out by a vet, as it is possible she may have a mild form of epilepsy. There are degrees of epilepsy in animals just as there are in humans (petit mal & grand mal). This can be controlled with medication. I have a 3yr old cat with a severe form of epilepsy, which is well controlled, and he's quite well and happy. It's worth asking the vet to check for this, it only requires a blood test. If hopefully it isn't a mild epilepsy, it still needs investigating. Hope all goes well.