A TSH level of 2.0 is well within the normal range (it is 0.4 - 4.0 mIU/L of blood).

I think that you are right in being sceptical about "adrenal fatigue" - it is a fictitious label used by many evidence-free alt/comp med people to explain many vague signs which they are not competent to diagnose or treat. Importantly, those signs can indicate possible health issues which an evidence-based health professional can investigate.

Getting the other levels checked out by your care team is a really good plan.