Can't figure out if my pomeranian is having muscle spasms or partial seizures?

She will be laying down sleeping and all of a sudden she wakes up yelping(screaming) and holding her right foot up. After the yelping its like she is a bit disoriented and takes a minute to put her foot back to the ground. I have been to the vet and we just began potassium bromide for seizures but I want to make sure that I am treating her for the correct thing.