Of all the cancers to have, this one is usually the easiest to remove and you'll have a very quick recovery as this cancer is usually self contained, if caught early. There will be an incision along your neck, and they try to make it in a crease, to remove your thyroid. You will probably have limited chemotherapy or radiation, which is focused on just one spot. And you will take thyroid supplements the rest of your life.
I have a girlfriend who just had her thyroid removed last month. She was never sick and looks healthy and normal and works part time, etc. She did start lactating last month, but that was caused by a side effect from a medication that caused her prolactin hormone to increase.
What were your symptoms that caused you to go in for evaluation? Honestly, you will be healthy and fine and this will have been a little bump in the road.