You should probably take them to the doctor. It sounds like this could be a seizure of some kind. If that is the case you need to see a neurologist, and maybe get an EEG. I'm not trying to scare you, but when a problem like this comes along you need to take care of it right away.
Yes, you should call your doctor right away. He may need to see a neurologist, but please don't ignore this. It could be really serious.