Hello ajwhiting,
Welcome to Apple Support Communities!
We want to help make sure your Apple Watch is correctly recording your data.
Start with the steps here to calibrate your Apple Watch:
"Check your settings
To make sure that your Apple Watch can get the information it needs, check these settings on your iPhone:
- On your iPhone, open the Settings app.
- Tap Privacy > Location Services.
- Make sure that Location Services is turned on.
- Scroll down, then tap System Services.
- Make sure that Motion Calibration & Distance is turned on.
- Continue with the steps below."
This Apple Support page has the full details and the additional steps to take: Calibrating your Apple Watch for improved Workout and Activity accuracy - Apple Support
We hope this helps get the calorie counts calculating as expected for you again.
Please let us know if you have further questions.
Cheers!