Hi Minnie
Like you and Mark I am hypothyroidic also. The medication has made a HUGE difference although I still seem to be colder than most people. My hair started falling out and became finer before I was diagnosed and my cholesterol level rose sharply. These were the symptoms that alerted my GP.
It will take a few weeks for the synthetic thyroxine to kick in fully, then you will feel fantastic.
Regarding the scalp, yes, the head and neck area on the side of my neck dissection all feels 'tight' and some parts are numb and others sore to touch.
From Helen, with love.