Query reg- shortness of breathe.

I have been having shortness of breathe for the past 6 months. Now its reduced a lot. i am having nose block at night and my CT PNS shows Deviated Nasal Septum and mild mucosal thickening is right maxillary and right inferior and middle turbinate hypertrophy, right of frontal sinuses hypo pneumatized with areas of ground glass density within. I have to take breathe through my mouth at times. i have also lot of burping and gastric issues. i always get some liquid or mucus in my throat(not sure from my nose or from somewhere else) which i have to clear every now and then.. I was very much PANIC about the current covid that, all symptoms appear more or less similar. I was getting panic that i would get pneumonia or some serious illness. I constantly check my Pulseoximeter and even it shows 95 for sometimes iam worried. I want to know the exact reason for my breathing issues. My CT X ray PFT taken in october were clear. How to find what causes my breathing problems?