Oh wow, Ed, this may be a good bit of information to give your doctor. From my experience 83 is low and it sure can explain why you’re tired. It’ll definitely be interesting to see the numbers when you wake up. A good way to test your theory.

A couple ideas which you’ve probably already considered, check your numbers throughout the day and keep a little journal of the results, making a note of how you were feeling at the time. Were you feeling energetic, were you feeling tired, etc. Then you can look for any trends. I really hope it helps you get to the bottom of this mystery! Let me know!