You could google calories burned standing vs sitting (if, during a normal day, you mostly sit for hours)-- sounds like the majority of what you were doing was that. I reckon the differential would depend at least somewhat on your weight. And then in your Fitness Tracker, there's the option for entering your own exercise. When you click on that, it opens a window where you can name it (ie, volunteer at school), put the minutes you did it, and the calories burned.
Although your legs might feel like they do after a power walk-- you did not burn the calories you would've for a power walk. Because you didn't get your heart rate up. If I entered it in my Tracker, I'd be very conservative about the amount of calories burned. To me, it's a real "gray area" where I'd want to be really careful not to overestimate. I'd probably use the lowest possible estimate of the difference between sitting vs standing.
Ruth in Cookeville, TN Central Time Zone
Promise me you'll always remember: You're braver than you believe, and stronger than you seem, and smarter than you think - Christopher Robin to Pooh
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