First thing to understand is that TSH is a pituitary hormone that is affected by so many things that, at best, it is only an indicator to be considered along with more important indicators such as symptoms, and also levels of the biologically active thyroid hormones Free T4 and Free T3 (not the same as Total T4 and Total T3). If TSH exceeds 10 it is called overt hypothyroidism. Less than 10, but over the range is called subclinical hypothyroidism, and a test for Free T4 is usually done. If Free T4 is within range, the patient is usually told that his thyroid status is okay and that symptoms must be due to something else. This is totally inadequate.
In reality the main value for TSH is to identify overt hypothyroidism and also to distinguish primary hypothyroidism (Hashimoto't Thyroiditis) from central hypothyroidism. With central there is a dysfunction in the hypothalamus/pituitary system that results in insufficient TSH to adequately stimulate the thyroid gland to produce hormone.
The right way to diagnose hypothyroidism is to evaluate symptoms, followed by tests for Free T4, Free T3, Reverse T3, Thyroid Peroxidase antibodies (TPO ab), Thyroglobulin antibodies (if TSH is high and TPO ab is negative), cortisol, Vitamin D, B12 and ferritin (a form of iron). Of course some symptoms are non-specific; however, there are a number of symptoms that occur more frequently with hypothyroidism. You have a number of those, so I recommend that you get the additional tests done. The reason for tests other than thyroid is that all of these can affect or be affected by thyroid status. Your Vitamin D is adequate, but B12 is best in the upper end of its range, so you can supplement to get there.
You can read about all this and confirm what I say by reading at least the first two pages of the following link, and more if you want to get into the discussion and scientific evidence of all that is recommended. Note that at present the link is down and being worked on.
When you go back for additional tests I suggest that you consider that a good thyroid doctor will treat a hypothyroid patient clinically by testing and adjusting Free T4 and Free T3 as needed to relieve symptoms, without being influenced by resultant TSH levels. Discuss all this with the doctor and ask if he will consider treating you clinically. If not, then you will need to find a good thyroid doctor that will do so.
When you have additional test results, please post results and reference ranges shown on the lab report and we will be happy to help interpret and advise further.
There are a number of things to discuss, but first what time of day was your blood drawn, and is the range for cortisol consistent with that time?
Your tests for antibodies were negative, so no evidence of Hashimoto's thyroiditis.
TSH is a pituitary hormone that is affected by so many things that at best it sin only an indicator, to be considered along with more important indicators such as symptoms, and also levels of the biologically active thyroid hormones, Free T4 and Free T3.
Your Free T4 is only at 27% of its range, which is lower than optimal for many people. Your Free T3 is at 58% of its range, which is a bit unusual for it to be higher than Free T4 in its range. So that makes me think of that your body is converting more T4 to T3, in an effort to maintain thyroid function as best possible.
So I suggest that you try to get your doctor to give you a therapeutic trial of thyroid med adequate to raise your Free T4 and Free T3 levels, and monitor the effect on your symptoms.. Also I suggest that with your ferritin level being less than optimal, you need to supplement with a good form of iron like Vitron C. Another contributor could be that your cortisol is less than optimal for early morning. This may be a contributor to your early afternoon "slump". It is hard to evaluate cortisol with only that singe test for total cortisol It would be far better to get a diurnal saliva cortisol (free cortisol) panel of 4 tests taken at different times of day. Most doctors won't order that, so the option would be to order a kit online from ZRT Lab, and pay out of pocket. Would this be possible to get done?
Since symptoms are the result of tissue thyroid levels and effects, it would be good to get the Reverse T3 test I mentioned. Reverse T3 is a mirror image molecule of T3, but is biologically inactive. It is a normal product of the conversion of T4, but in some circumstances excess Reverse T3 is produced, which blunts the effect of Free T3. You can get lots of info on this starting in recommendation 9 in the link above.
In order to try and answer your question about medication, where are you located?
If you are able to get the doctor to test for Reverse T3, you need to get a Free T3 done from the same blood draw, in order to determine the ratio of Free T3 to Reverse T3.
I would ask the doctor for a trial of thyroid med, specifically about 50 mcg of a T4 med, as a start, and see what that does for your Free T4 and Free T3 levels after 4-5 weeks. If you get agreement for this it would be the best time to also test for Reverse T3, since you would be re-testing Free T4 and Free T3.
In addition you could supplement your B12 with about 500 mg daily. Also I suggest supplementing your ferritin level with a good form of iron, about 25 mg daily. Along with that I suggest taking about 500 mg of Vitamin C to avoid any stomach issues from the iron.
Please keep in touch and let us know the results from any additional tests.
Okay, that is a start at least. Please be aware that when starting on a small dose of thyroid med, that is not additive to your prior levels. Instead the hypothalamus/pituitary response will be to reduce your TSH output, which then will reduce your output of natural thyroid hormone. Since serum thyroid hormone levels are the sum of both natural thyroid hormone and thyroid med, the net result is often no change, or even a slight drop in levels. Only when TSH is suppressed enough to no longer stimulate natural thyroid hormone production will serum thyroid levels reflect further increases in thyroid medication. So, knowing this you can prevent the doctor from deciding that the 25 mcg did nothing for you, and nothing further is needed.
Please keep in touch and let us know how you are progressing with getting the additional tests done and whether the doctor continues to increase your med dosage. We will also be happy to review any test results and help interpret and advise further. No worries, mate.
I think you also need to ask your doctor for his interpretation of your cortisol resut. I think it is a bit lower than optimal.