It does sound as if you are stull under-medicated, but really you need to check iron, ferritin, folate, vitamin B12, Vitamin D.
Having said that, it would be good to have the lab's ranges for the tests you have had, because quite honestly in most labs that T4 is not very high.
Dizziness is not at all unusual amongst Hypothyroid patients who are not adequately treated.
You have a lot of hypo symptoms and that TSH really is not very helpful if, for example, your pituitary were not functioning correctly and not producing TSH as it should. a low TSH plus low Thyroid hormones T4 and T3 would suggest this, in which case your thyroid replacement is inadequate. 25mcg would be nowhere near enough for most people except those who are VERY sensitive to thyroid hormone, in fact a dose as low as that could well make things worse as it can suppress the TSH (Thyroid Stimulating hormone) which in turn will make the thyroid's own output even lower. This will result in your feeling worse, not better.
So my first suggestion would be to find out the ranges used by the lab (they should have them on the result sheet) and ask for a T3 test. If they cannot or will not do this test, then you can actually have that tested privately, information is on the main TUK website:
You can select whichever you wish, I personally do a home blood test from Blue Horizon. As a TUK member you can also get a discount.
This would be a starting point to finding out how to get better.
Hope this helps.