https://www.sciencetimes.com/articles/25439/20200423/silent-hypoxia-bringing-covid-19-patients-closer-death.htm It looks like it's a good idea to monitor your oxygen levels, especially if you are an at-risk group.
Science Times "Silent" Hypoxia is Bringing COVID-19 Patients Closer to Death Coronavirus Disease (COVID) pneumonia causes silent hypoxia, lowering the oxygen levels in a patient’s tissues. Unlike acute hypoxia, silent hypoxia doesn’t make anyone feel sick until it hits. When it does, it’s too late, unless a pulse oximeter monitors oxygenation levels.