Since Returning From The Desert In Utah, I Have Had

Since returning from the desert in Utah, I have had my nasal sinuses full. My ENT doctor has scoped my nasal cavity, throat and esophagus 3 times and has found nothing physically wrong. I still have the small amount of mucus collecting in throat. Also, My tongue will enlarge as I speak and if I am eating it will effect my swallowing and seems that I might choke on my food. What could be the cause of these conditions?