btm66
I'm sure you have been diagnosed by now, but in case you haven't.
At 18, you more than likely would have Type 1 diabetes, unless you are overweight, then MAYBE Type 2. However, the symptoms you gave does not agree with diabetes. The most common symptoms are thirst, increased urination, blurred vision, sweaty shaking, and in the case of Type 1, weight loss.
There are things you can do for the thyroid instead of Synthroid, which I've heard can eventually kill your thyroid. Kelp and dulce can help. Also, Armour thyroid. If you want to get rid of it, you may want to do
Dr. Schulze 's Incurables Program.
Hope this helps.