Normal T4, low tsh

When I was diagnosed, my disease was caught quite early before my values were too much out of range. I  was started on 10 mg of Methimazole and it immediately brought my FT3 and FT4 into the mid to high normal range and stayed there while I continued to take 10 mg of Methimazole.  My TSH however remained at less than 0.001 for two years.  Then I read a research article about the benefit of hyperthyroid patients taking 3,000 to 4,000 mg of regular L-Carnitine per day.  I also became aware that I had a vitamin D deficiency.  I added both those supplements and my TSH began to rise for the first time in 2 years.  It was only then that my Endo lowered my meds dose.  I then tried different carnitines and tried Acetyl-L-Carnitine and my TSH shot right up into the normal range and my Frees dropped down to the bottom of the normal range.  I have adjusted quite a lot but kept my values fairly constant since then.  My Endo adjusts my Methimazole, I adjust any supplements.  I currently take 2.5 mg of Methimazole four times a week.  I was down to 3 times a week but then had a major stress at work so it affected my values and I went back to 4 times a week.  I feel fairly good from my thyroid disease point of view and I could do this the rest of my life and be happy with it.