What's the reference range for the T4? Ranges vary from lab to lab and have to come from your own report. Also, Total T4 is considered to be an outdated test and not very useful, but with the reference range, it would be a start. Are those the only thyroid related tests you had done?
Do you have symptoms of a thyroid condition? If so, would you, please, list them?
Your symptoms indicate hypothyroidism... can you get a copy of the actual report?
Do you happen to know your actual ferritin result? Ferritin is the iron storage hormone and iron is necessary for conversion of T4 thyroid hormone to T3...
Your T4 does seem to be low compared to ranges we, typically, see, but we'd expect to see TSH much higher with a T4 that low. The results may be indicative of Central, or Secondary, hypothyroidism, which is a problem with the pituitary gland, not the thyroid. You should discuss this with your doctor.
If you can get a copy of the lab result, it would very helpful.
When you get the report, it would be great if you'd go ahead and post reference range for the T4, since results have to be compared to the range used by the lab that analyzed the sample.
Your ferritin, at 43, is too low, so it's good that you're supplementing to bring iron levels up. Low iron can cause severe tiredness.
Have you had vitamin B-12 tested? Deficiency in B-12 can also cause horrible fatigue. The voice issue sounds thyroid related.
The NHS does recognize Central/Secondary hypothyroidism, but they may not, as long as TSH is in the "normal" range. We have had numerous members from UK that have, also ended up having to go private in order to get proper treatment, because of stringent NHS guidelines that specify "in range" labs to be "just fine"...
I'll look forward to seeing your labs and reference ranges.
My T3 is 5.9 TSH 0.5 and T4 is 7.3 - is this normal?
While all of your results, actually, fall within the normal ranges, I can see where you would have hypo symptoms, because your FT4 is only at 3% of its range, which means your thyroid is not producing as much hormones as your body needs.
Your T3 is only at 33% of the range, which, also is not enough for what your body needs. Furthermore, the way it looks, the T3 result if for Total T3, not Free T3. Free T3 is the hormone that's used by individual cells in your body.
I stand by what I said originally... you should talk to your doctor about Central hypothyroidism.