Hello there, My son has had a severe sinus infection for about two weeks now. He used amoxicillin for 10 days and the infection is not gone yet. Plus, his left year is plugged, he feels pressure there and can t hear good. Today he complained of feeling nauseuos. He is adult, 38 years old, does not have insurance, and cannot afford himself to go to see a doctor. Do you think I should take him to see one or recommend some over the counter medication?