Free T3 is important for everyone. Even young people can have an issue converting FT4 to FT3. You can't know without testing it.
Rule of thumb is to get FT4 about mid range and FT3 into the upper 1/3 of the range.
Can you verify the range for that FT4? It's a very narrow range and we don't normally see anything like that. If the range is correct, you're slightly higher than mid range, which could indicate that you really don't convert well, because your symptoms aren't being alleviated. FT3 correlates best with symptoms; FT4 and TSH do not correlate.
Oh and here are the other ranges:
T4: 4.5-12.0
TSH: 0.5-4.3
My free T4 range says: 0.9-1.4. I also asked my doctor about T3 and they told me that since I was so young I shouldn't be worried about it. According to them, mostly older people who have had the disease for a long time have a problem converting T4 to T3. Also, I am only on 112mcg of the levothyroxine
From your labs and symptoms it is most likely that your dosage is inadequate, or you need a different med. Even though TSH is a pituitary hormone and affected by numerous variables, when it is as high as your, it is a good indication of hypothyroidism. To better understand your status you need to get tested for the biologically active thyroid hormones, Free T3 and Free T4 (note that these are not the same as Total T3 and T4).
In addition, since hypo patients are frequently deficient in other areas as well, I suggest that you also test for Vitamin D, B12 and ferritin. From all these tests we can help you understand if your meds need to be increased, or if you are not adequately converting the T4 to T3, and you need to add some T3 to your meds. Dependent on your other test results you might need to supplement to raise your levels.
When test results are available, please get a copy of the lab report and post your results and their reference ranges so that members can help interpret and advise further.
I am confident that we will find the answers and you will be able to get relief from those symptoms.
What is the reference range for the Free T4? Ranges vary lab to lab, so have to come from your own report.
Your TSH is quite high and indicates that you are still hypothyroid. Your symptoms bear this out, and I suspect that your FT4 will, too.
Your doctor is not ordering the proper tests for you. You need to have Free T3 and Free T4, along with the TSH, every time you have blood work. When a lab report says just "T4 and T3", the tests are total and are considered obsolete and of little value; pretty much a waste of money.
What dose of levothyroxine are you on, and how long have you been on it?