Hi ,
I just wanted to jump in and add that blood oxygen levels can fluctuate based on a number of conditions.
As Rebecca mentioned; heart and lung conditions are some of the most common conditions. In addition, sleep apnea, high altitudes, and chronic illnesses can all interfere with one's blood oxygen level.
Do you check yours regularly at home? I found a pulse oximeter (that goes on your finger) to be quite inexpensive and helpful.
It's important to bring your concerns to your healthcare provider's attention. (perhaps keep a journal of your readings at home).
Wishing you well, Doreen (Team Member)