You can only get reliable reading of O2 levels when sleeping with a recording pulse oximeter taped to your finger with alarm off. Your doctor can order it and it can be home in your own bed. Our O2 levels can drop once we are sleeping as most of us breathe more shallowly.

If you are awake, your reading is likely higher. Since I started sleeping with O2, my sleep has really improved. I strongly urge you to ask your doctor about a home overnight O2 study.