Possible trigeminal neuralgia or Temporo-mandibular-joint(TMJ) problem. Do not worry, can be treated with medication. Do consult doc.
I have had this happen to before too. i dont know for sure what it is but i think it was from alergies, my sinus infection i think.
PLEASE GO TO THE DR. it could be many things. have you had any pains in chest, nausia,etc..any pain, discomfort in arms and hands? take my advce and go to hospital.