Levothyroxine with odd test results TSH/T4

I’ve been on varying strengths of levothyroxine for about 35 years following a thyroidectomy for hyperthyroidism treatment. My most recent labs showed TSH of 0.027 (pretty much non existent) and a T4 of 1.92 (off the usual scale high). These results would seem to point to subclinical hyperthyroidism, BUT my heart rate stays in the upper 50’s to upper 60’s and I can’t lose weight no matter what I do. I’m set to repeat the tests in 6 weeks. Any thoughts??