brain fog,poor mem/conc, constant mild headache,thyroxine hlepd for while

Hi,I am 23 years old.
I have diabets for 12 years now. For years maybe more than 6 I
have these symptoms: brain fog, pure memory, lack of concentration,
mild headache in the top-rear part of my head. I also feel fatigued
and unmotivated quite often. I am thinking quite slow, finding the proper idea, word or whatever but quite later than I needed it.I have difficulties finding words, or recalling things that I am sure I knew some days ago and I am sure that this is beyound the normal. I am sure because I compare to others (friends, coleagues, etc.) I still have kind of normal reasoning but I feel I am losing my identity (personality). See, I had difficulties finding this word (even on my mother's tongue).
A few weeks ago I decided that it is high time that I do something about the problem and started browsing the web. I found that a common cause for kind of similar problems is hypothyroidism. So I started taking small dose of L-Thyroxine.Whatever my problem is this medicine had a thremendous effect, unfortunately for few days.
During these few days I was totally different in my cognitive capabilities, maybe all the symptoms were gone, not to mention that  
I had extremely more energy than before. However short after that
my symptoms restored to the previos state and I started getting the symptoms of overdosing - hyperthyroidism: palpitations, even ache in the heart and dry skin. So it turned that hypothyroidism hardly could be the cause for my condition. It must be something that the thyroxine has positive (as side effect) effect on but not a hypothyroidism. Please help.

[CCF-Neuro-M.D.-CS]

You need to seek the care of a neurologist. They can evaluate you and perhaps perform neuropsychological testing and you may need a imaging study of your brain (such as a MRI). Your thyroid function should be tested prior to starting medication. You may have taken an excessive amount, but could still be hypothyroid. Also your B12 level should be assessed. I would strongly recommend that you obtain care under the guidance of a physician. Good luck.

[BigSamlkpt]

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