Current medical guidelines state that we should test our thyroid function every 5 years. Mine was tested at 51. My doctor realized that it had never been checked. I encourage everyone to get tested.
I think I've been having problems for the past 5 years

When I think of the time I spent suffering and trying to cope with depression I just want to cry. I was feeling apathetic and feeling like I wasn't resilient. Like if one more problem came up I couldn't cope with it. That wasn't normal, but I never realized anything physical was wrong. I thought I was just lazy. Increasing the antidepressant didn't help.
Things are better on the thyroid medicine and it's a blessing.
I think every woman in their 40's should demand a thyroid test. Maybe then the insurance companies would consider it a routine expense and cover it 100%.
Sue