I've noticed my SPO2 levels usually range from 96 to 98, but sometimes they drop to 90 before going back up to 96. I'm not sure which reading I should pay attention to. Also, my BPM is consistently over 100. Meanwhile, my mom, who's 51, has a normal BPM between 72 and 80. I'm worried if these symptoms could be related to any heart or lung issues, especially since I haven't had COVID. Could you give me some advice on this?