Can sinus problems cause lightheadedness?

Yes as it's all connected but its rare and you would have to have something serious or infectious for it to travel that far. Often the bacteria that cause bad breath and ulcers, can travel into the...

because it probably has alot of pollen,and pollen is usually the main cause of of sinuse swelling and other issues.

Definitely - specifically and upper wisdom tooth. Often the roots of wisdom teeth run into the sinus cavity and even some of the upper molars. If the tooth is abscessed and infected, it can cause...

The drainage makes you gag or nausiated...it'll make you feel sick to your stomache and possobly through up, yes.

A broken nose with a deviated septum can possibly cause sinus trouble. For appropriate diagnosis and treatment, please see your physician asap.