From what u said, it will be facial palsy. You may have exposed to cold wind through ears or would have had a ear infection recently. Meet a doctor for anti inflammatory medications as well as a physiotherapist for electrical stimulation of the facial muscles and exercises for the same. Stimulation will maintain the properties of muscles till the power comes back. Exercises include blowing whistle, balloon, drinking in a straw etc which strengthens your muscles. U can expect recovery within 3 weeks if right treatment is taken at right time.