Brainfog, Fatigue, red blood cells, and CPAP

so i have known for the past 4-5 years that i have had worsening brainfog and fatigue. i chalked it up to my commute and long hours but last year it got so bad i went to the dr and said they had to do something because i was only operating at about 60% of my normal cognitive abilities. they know i am on benzos and said that could be part of it (but not all of it and not from a crippling perspective). I told them they need to run the gauntlet of tests and find out because i cant grow into my career like this.

i have had blood work ran twice in the past 12 months and the only thing out of tune is my red blood cells. they have been coming in high. they mentioned that is probably the cause of my brain fog and cognitive decline. they assumed i had a blocked artery in my heart or that i had sleep apnea. if you seen me you would wonder who the heck gave them a medical license.

thank god i upgraded my insurance because the sleep test was $2400 alone for a single night but came out to an easy $25. Out of mild, moderate, and severe apnea, they allege i have moderate apnea (though the second part of the test where they give me was inconclusive other than my oxygen levels improved)

post sleep test i went to the cardiologist who actually kicked me out of her office and let my dr know that sending me there was a waste of everyone's time  they told me "dont drink, get off the benzos, use the CPAP, and not only will those blood cells normalize but your brainfog will go away"

Ab-so-lute-ly....let me just turn this wine into water really quick and ill get right to it quick as a bunny

My questions are:

• Has anyone had issues with their red blood cells during benzo use?
  Has anyone here been prescribed a CPAP DURING withdrawal and did it help or hurt your recovery? what about brainfog?
  Has anyone been treated for underlying oxygen issues (asthma, apnea, lung disease) and seen brainfog improve?
  
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