What causes sore throat every morning and light headed?

Mouth breathing: If you mouth breath while sleeping it can dry your throat making it feel sore. Nasal congestion at night can also effect your sleep and might make you feel lightheaded. If the room you sleep in has very low humidity it can also cause soreness. Try a humidifier in your bedroom and make sure it's turned way up. Also consider an appointment with an ENT doctor for an airway evaluation.