It is indeed difficult to diagnose your condition as it needs a proper examination. You need to get a thorough evaluation done from a good ENT specialist
. Till then, you can try with steam inhalation (2-3 times/day), drink plenty of warm water as well, use saline nasal drops (2-3drops, 3-4 times/day) to get rid of the foul odor.
Dr. Naveen Kumar