I'm sure that the doctor has some testing planned for you today, but you should also request that you be tested for free T3 and free T4 (FT3 and FT4, not total T3 and total T4). If the doctor resists, then you should explain that you want to know the levels of the biologically active thyroid hormones, FT3 and FT4, and insist on testing for them. Don't take no for an answer. You're the customer. if you have never been tested for the thyroid antibodies then also ask for TPO ab and TG ab tests.
Since hypothyroid patients also frequently have deficiencies in Vitamin D, B12, iron/ferritin, and selenium, it would be a good idea to have that done as well. Another informative test would be an ultrasound of the thyroid glands.
When results are available, please get a copy and post results and reference ranges shown on the lab report and members will be glad to help interpret and advise further. It is a good idea to always get copies of lab reports and write on there how you were feeling at the time and what meds you were taking. These then become very valuable references.
I am on synthroid 100mcg. I had extreme fatigue and weight gain which is why I was tested and put on meds. I was just upped from 88 to 100mcg 4 weeks ago. I am getting tested today to see if that dose is ok. My pulse was in the 70's until after I had a baby 2 1/2 months ago.
Please post your thyroid test results and their reference ranges shown on the lab report. Are you taking thyroid meds? If so, what type and how much daily? Are you experiencing any other hypo symptoms?