Ask you dr. if you couldn't have a "deep seeded" sinus infection. The reason it got better while on antibiotics is because the infection was being battled. You could have infection with little of NO symptoms (ie.runny nose, stopped up head, etc.) and still have an infection. It makes sense to me, but ask you dr. also, has suggested a CT of your sinus's? It make find the problem. worth asking the question. Good luck :)!