Not mad at all. That's the way being hypo affects you. Your brain needs a lot of T3, so if your T3 is low, it's normal that the brain doesn't work very well.
The TSH - Thyroid Stimulating Hormone - is a pituitary hormone.
When the pituitary senses that there's not enough thyroid hormone in the blood, it secretes TSH to stimulate the thyroid to make more hormone.
When the pituitary senses that the thyroid has made enough hormone, it lowers the secretion of TSH.
Your thyroid cannot response to the stimulas of the TSH, so your hormones have become very low, and the TSH high. And you have to take thyroid hormone replacement (T4 and T3).
If you take enough T3, the pituitary is going to sense it in the blood, and stop secreting TSH BECAUSE YOU DO NOT NEED IT. That is the most important thing to remember. You do not need TSH anymore because you are taking enough T3.
Low TSH, when you are on thyroid hormone replacement, is not any sort of a problem. It will not affect your heart and it will not affect your bones. TSH only 'communicates' with the thyroid gland, nothing else. So, if you have enough T3 in your blood, you do not need TSH, so the pituitary will stop secreting it.
Doctors just do not understand that. They think that an under-range TSH means you are over-medicated. But it doesn't. The range is only there for the purpose of diagnosing (and even then it's not much good). It is not supposed to be used for dosing.
Print this out and look at it when you feel confused. lol