Thyroid – full?

During my yearly physical, my doctor said that she thought my thyroid was full and ordered blood/lab work. I meant to ask her at the appointment what a full thyroid would indicate, but I forgot.

I have a high metabolism, great cholesterol rate and would say that I am in fairly good physical condition.

But here’s my question(s) – What does the thyroid do and what would a "full thyroid" mean? I’m assuming that because she ordered tests, it must not be good. What are the raminifications and/or treatments if I do have a "full thyroid"?

Any help would be appreciated! Thanks!