Uhm. The reason your TSH is normal is because of the synthroid, so KEEP TAKING IT! Your doctor is a QUACK!
Ask you see a specialist or something. Find another doc. There are specialists listed here:
http://www.thyroid-info.com/
Click on "top docs" to see if there is one in your area...
Duh... it's a hormone replacement. I can't believe the stupidity your doctor is showing here.... she could kill someone!!!