Suggest Treatment For Stage 4 Papillary Thyroid Cancer

I am a 49 year old woman who had a radical right and lateral neck dissection optional 2012 due to stage 4 papillary thyroid cancer. It s been two and a half years since my radioactive iodine treatment/ ablation and I ve been monitored by my endocrinologist carefully. My Thyroglobulin levels have been undetectable since treatment. My doctor has changed my Synthroid dose about five times since the initial dosage. Right now my TSH level was .7 and she said it wasn t in the right range of .1-.5 however it was closer than it has ever been in the past two years. I am wondering it is taking so long to get it within the proper range and what the side effects or dangers of not being in the right range is? I also have a lot of fatigue, forgetfulness, Charlie Horse, menstral irregularities, severe hair thinning, to name eat worst. Is there something else going on or that I should have checked/ be looking at that would cause this? Or is this to be expected? Thanks, Leslie