I had this a couple of weeks ago coming into SYD. The pain was really terrible and lasted for 3 or 4 hours afterwards I tried everything to clear my ears but they just wouldn't pop. I didnt even think my sinuses were blocked but I had been in an extremely cold hotel room so they may have contracted. It was the first time in a long time I had had any probs with my sinuses but it felt like daggers going through my head. Sudafed or some other pseudoephidrine based drug should fix it.