"My O2 level sometimes drops into the mid to low 80’s. Is this drop in O2 dangerous, or is it better to keep it over 90? Can I suffer some type of damage as a result of the repetitative 'drops'. (My level will go over 92 while seated, so i take the cannula off, when I get up to do something like make tea or wash my hands, I forget to put it back on. I am tending to get light headed and feel 'frail'. I've been checking my SpO2 after getting back to my oxygen."