Why is my head going all Poltergeist on me
The experience you describe is not a common experience but meditators do get very uncommon experiences due to sudden outburst of past Karma / Snakhara. When you have stopped creating new Karma though Vipassana sometimes deeply hidden karma suddenly pops up to give results. (Many times cited by S.N.Goenka in his lectures.)

Also if would be an idea to also see a doctor and perhaps a serious meditator too to rule out any medical condition just be on the safe side.