Others on this forum are more experts when it comes to hormones..especially Joe...so they could probably offer way better advice.
I read that in order for thyroid to function properly you need cortisol. I read that people with issues of fatigue are diagnosised with low cortisol only after they are put on thyroid medication and they don't feel any better.
The symptoms you described sound more like hyperthyroid. It's possible now that you are on cortisol you don't need as much of the thyroid medication.
To be safe I would probably get another 4x daily cortisol and thyroid test to see how they are funcutining.