same problem every time:-(
I get them in the mornings mostly, seems to be a similar pattern to you, I am undiagnosed as tests come back neg...I think I also have thyroid they come back Neg .....
I get chills at odd times, but not in the pattern you describe. It's a good data point to bring to your next dr's appointment.
As I am preparing for a dr's appointment, I make notes of symptoms during the week or so before the appointment -- whenever a symptom pops up, I jot it down so I don't walk into the office and go blank, as usually happens. (Brain fog and stress from going to the MD.)
My body temp has been chronicly low since I got Lyme, usu 96.5 to 97.0. I may have a slight thyroid deficiency (which I think Lyme can also cause) but the thyroid pills upset my stomach, so I didn't take them long. Might try again sometime.