YEP! I am with you on this. I had to take 20 days of antibiotics for last infection. When I started Remi last year I got a full blown sinus infection, took 10 days of Amox and felt better. Made it all the way to January and just wasn't feeling right and couldn't figure out what was going on. Turns out only the maxillary sinuses (lower ones over upper teeth behind the cheeks) and 1 ear were infected. I think I did not get the crap all out the first time. Well as I finished the first 10 day run I was not feeling better, in fact some things felt worse, like my ear. Did another 10 days and when it was all finally clear I then realized how bad I was.
I saw you try try the netty pot, I have tried to use the squeeze bottle version. I could suggest taking a sinus or allergy pill as my docs have given me to help keep things a little drier to try and keep the infection risk down. I also use flonase daily, for the same reason. I think the infection got itself in deep before I realized it. I am still learning about how soon to get to a doc when starting to feel rough.