Hello, and welcome to the community.
You didn't mention sinus rinses. You can purchase a NielMed bottle for around $12 at most pahrmacies. NielMed is the only rinse bottle I know of. Most of us here prefer the bottle over the neti pot because you get a slightly stronger flow that helps clear away more of the gunk. You can use the bottle a few times a day (up to 5) while you are working. I would recommend that last one be done after your shower at night.
What antihistamine are you taking? Most of us don't find benadryl very effective and you have to keep taking it every four hours. We most prefer Zyrtec (generic is available as well). It costs more than benadryl, but you only take one a day.
Lastly, there is one over the counter nose spray you can use, NasalCrom. It will have to be used every 4 hours, but it would be better than quitting your job.
If you could swing a doctor's visit and get some scripts for nasal sprays they would be much more effective for you. There might be a free clinic in your area you could go to. I know our smaller city has at least 2. The doctor should be able to help you with assistence programs for any medication he prescribes. Assistence programs are bountiful right now.
Take care and feel better.
Sonya
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