Agreed for sure on copies of your labs. I keep them all. Also make sure to ask for Free T3, as that is the active thyroid hormone. Some of us (I am one) do not convert T4 to T3, so we have to take a combination thyroid replacement. (I am on both Synthroid and Cytomel) It is very frustrating, as so many endo's are not versed in optimal thyroid treatment, especially for athletes.
Good luck and take care.