For your consideration ...
If one is never tested, one will never have COVID.
Get yourself some hot sauce, Tabasco, hot chili peppers, jalapenos, or the formidable "ghost pepper". And, when after your eat them, it should open right up those sinuses for a brief respite and free breathing, and give you a chance to blow your nose to get rid of the buildup of mucus. After which, have a glass of whole fat milk on hand, or some butter, to quelch the burn/heat after you clear your nose. You could also use a vibrator, (not that kind ; ), but if that is all one has ....), and use it on the bridge and sides of your nose. The high frequency vibrations will loosen up and open the nasal passages helping to induce drainage as well as getting you to sneeze which will help to expel that excess mucus. Oh yes, it will feel extremely funny and weird, and make your eyes water, but it does work.