I want to emphasize the importance of seeming an ENT. I also saw an ENT, but very early in my journey. I also had sinus surgery. After recovery was the first time in my life I could breathe fully through my nose. I had no idea - it was like being blind and being able to see for the first time, except I had no inkling others could see. That actually opened up a realization that the sinus issues they fixed had led to chronic infections, which upon over a year of various treatments I finally cured, leading to an incredible uptick in life quality. Turns out some non trivial percent of people have chronic sinus infections due to poor nasal air flow, and having an infection next to your brain doesn’t make you feel very good. But they’re also very hard to diagnose.

The ultimate treatment that worked was daily sinus irrigation plus a treatment of sinus irrigation with a specific type of topical antibiotic that can break down biofilms. I would mix the antibiotic with saline and topically irrigate the sinuses. The benefit was it wasn’t a systemic antibiotic so it didn’t screw up my entire system. I eventually read this book:

Harvard Medical School Guide to Healing Your Sinuses (Harvard Medical School Guides) https://a.co/d/dpDZwba

And they had a brief section on topical antibiotics. I asked my ENT and he said it’s a vastly superior treatment but most people refuse to do sinus irrigation so he just gives pills - which he said are usually partially effective, and thus temporary, due to the presence of biofilms.

Anyways long story - I recommend everyone assume they have a sinus infection and visit an ENT for a check up, and to take up the practice of sinus irrigation as a preventative measure especially during and after an upper respiratory infection. Apparently when baths were the common way of cleaning (especially before modern plumbing, using rivers and lakes), sinus irrigation was generally part of the routine by just dunking the head and filling the sinuses then expelling the water and other stuff. There’s a now lost English word for it that I can’t recall any more, but with showers and modern Victorian hygiene that dispensed with a lot of traditional hygiene, we’ve lost the practice.