on the upside - hashimotos is usually pretty straightforward to diagnose
antibody tests for 2 - or 3 different antibodies - along with all the usual thyroid hormones - usually yields a pretty clear result - especially after several tests
i am no doctor - but in your case i feel it would likely show up in at least some of those tests as antibodies - or at least way out of whack T3 or T4
that said inflammation in the body is known to interfere with the proper conversion and receptor function of all sorts of hormones and certainly thyroid hormones. This means that your thyroid gland may be making enough hormone and it may not be converted to the active form efficiently
- eg high T4 low T3 and hypo symptoms - or high rev T3 and again - and again hypo symptoms).
alternately, the levels of all hormones could be OK - but the receptors are just not working properly due to all the inflammation - and so tests would be OK - and yet you could have hypo symptoms
just some guesses / possibilities to check out
-do you have any recent tests of inflammatory markers or clear inflammatory symptoms? ( almost guaranteed with Lyme et al )
- anti-inflammatory diets and lifestyle changes can help with this
- there are also thyroid specific supplements and co-factors that can help with various steps in the chain - but it requires some reading as the thyroid metabolism is not a simple thing
i usually recommend this guys site as a decent place to start - i have no affiliation - but just find it about
the most useful without going crazy deep
https://www.restartmed.com/free-resources-downloads/