Sounds like you have a head cold. This can be from a virus or bacterial infection and it will make your teeth hurt. As you are feeling lightheaded, your inner ears may be affected.
You can do steam inhalations to help clear the congestion. A hot bowl of water with vick or olbas oil and your head covered with a towel over the steamy water. Take care not to get scalded. If you find that you are bring up green or yellow mucus, this is a sign of an infection and the doctor may prescribe you with an antibiotic if he feels this is a bacterial infection.
There is no cure for virus problems, but sometimes yu can get a secondary infection that may need to be treated.
Wishing you a speedy recovery.
Believe it or not, it can be a sinus infection. Or it could be something going on with your ears. Both conditions cause a lightheaded feeling or stuffed head feeling. And a sinus infection can cause the teeth to hurt. (I actually get a gum infection with my sinus infections.) If you have an infection, only a prescription of antibiotics will help.