Sinus infection is characterized by an infection of the lining tissues of the sinuses within the skull. The resultant inflammation leads to blockage of the openings that allow drainage of fluid from the sinus. Symptoms can include pain or pressure sensations over the involved areas of the face along with tenderness and swelling. Stuffy nose, or nasal congestion, can occur as well as drainage or discharge from the nose. Cough may be present, and sometimes patients have fever.

Other symptoms can include earache, pain in the jaw or teeth, nausea, sore throat, and a decrease in the sense of smell. Discharge may be present in the back of the throat that produces cough and bad breath. Sneezing, an unpleasant taste in the mouth, visual disturbances, and a feeling of fullness in the ears can accompany a sinus infection.

Source: http://www.rxlist.com