Calibration Makes Things Worse?

Hello! I received my Apple Watch 3 as a Christmas present and have been loving it! Through the winter months I used it to track treadmill activity, and the calorie, and distance totals would be very close to what the Nordic track would indicate.

Recently it has started to really undercount distance every time, by 20-30%, and often but not always, under count calories. This started happning after the weather has turned nice and now I use it to track brisk outdoor walks.

If the outdoor walk triggered an auto calibrate it seems like it almost changed for the worse? The treadmill speed it records now in error seems to be similar to the slower but still brisk pace I have when walking outside. Advice?

As a side note, sometimes, despite a brisk exercise, it fails to record exercise minutes. I want to keep my 2021 three-rings streak going and have had to redo exercises!!!

Thanks!