What Causes Sleeplessness Inspite Of Normal TSH Level?

I was on 125MCG Synthroid for years and felt great. My Phys. Asst. watched it closely and I always felt great. She said I did best on the high side of normal with was normally about 3.5 (that was when the norms were .9 - 4.4 or so. She is no longer there, I went in to see the primary dr being tired, worn out (this was after he dropped my dosage about a yr ago to 100 mcg). Just exhausted all the time, can t sleep 2 night. He did TSH and it was .9 and would do nothing because it was within normal range. TOld him Kelley had worked with me for a couple of years to get it to the point I did the best and to please read her records. He s refused to do anything to change it because I m within normal range. I think I need to go back to my Endocrinologist. Just curious though & can never keep it straight. IF he were to get my TSH up some, would my Syhthroid dosage go up or down. I was thinking it should go up but I m told it should come down ???