The confusion is with your doctor. Thyroid medication dosage should not be determined based on TSH. When taking thyroid medication all at once, it is quite different than in the untreated state where there is a continuous low flow of thyroid hormone. This usually results in suppression of TSH when taking thyroid med dosages adequate to relieve symptoms. A suppressed TSH, like you have had, does not automatically mean you are hyperthyroid, unless you have accompanying hyper symptoms due to excessive levels of Free T4 and Free T3. Apparently you did not have hyper symptoms. So, if tested for Free T4 and Free T3, please post those results and reference ranges shown on the lab report.
A good thyroid doctor will treat a hypothyroid patient clinically by testing and adjusting Free T4 and Free T3 as needed to relieve symptoms, without being influenced by resultant TSH levels. Symptom relief should be all important, not just test results, and especially not TSH. In addition, hypothyroid patients are frequently deficient in Vitamin D, B12 and ferritin, so you need to get those tested and then supplement as needed to optimize. D should be at least 50 ng/mL, B12 in the upper end of its range, and ferritin should be t lest 100.
You can read about all this in the following link. I suggest reading at least the first two pages, and more, if you want to get into the discussion and scientific evidence for all that is recommended. You might be able to get your doctor to read the paper and revise his treatment of you. Many of us have found that we needed Free T4 at least mid-range, and Free T3 in the upper third of its range, and adjusted from there as needed to relieve symptoms. If you doctor is unwilling to do the needed tests and treat clinically, then you will have to find one that will do so.
http://www.thyroiduk.org/tuk/TUK_PDFs/The%20Diagnosis%20and%20Treatment%20of%20Hypothyroidism%20%20August%202017%20%20Update.pdf