Is there a connection between b6 toxicity and thyroid issues?

In the fall, I developed a series of odd symptoms, including vertigo, then tinnitus, brain fog, fatigue, muscle spasms, etc. as well as some of the common symptoms of hypothyroidism, including hair loss, constipation, etc. After seeing multiple doctors, one suggested I get my B levels checked. All were normal except for B6, which are extremely high (>250, with normal upper range of 21). I don't take supplements, really. An occasional multi-vitamin. At the same time, my TSH levels are on the rise. My normal is below 3 and they are now at close to 4.5. I've been taking NP Thyroid for more than 10 years at a very low dose. I can't figure out why my B6 levels would be so high, or how they might relate to other test results.