I'm really concerned about my oxygen levels; my SPO2 seems to fluctuate from 89 to 99, and it's usually more stable between 92 and 95. I also have frequent throat infections because of sinusitis draining into my throat and occasionally deal with upper respiratory infections. Could these issues be affecting my oxygen levels? My recent master checkup was normal chest X-ray, ECG, and echo all clear. Ive been using a fingertip home pulse oximeter for measurement. Lately, the throat infections are happening more often. What should I consider or do next?