I've been using a pulse oximeter to help in pacing and to see how I react to various activities and positions. It seems that after doing activities I consider moderate (such as 20 minutes picking strawberries while sitting down, then 10 minutes of tying back plants a few hours later) my resting heart rate goes up to about 110. Usually it's about 80 if I've been sticking to mild activities. This elevated "resting" heart rate seems to last for a couple days after the moderate activity, even if I then become mostly inactive. During that time, if my heart rate starts falling, my oxygen % also falls to the low 90's, sometimes the high 80's depending on my position. Any idea what biological dysfunction could cause this days-long elevated resting heart rate, such as in better understood disorders? I haven't been able to find anything useful on google.