Have you mentioned this to your doctor? If you are having blood tests it might be worth having one for thyroid as well. An underactive thyroid can result in very dry skin.
The thing about the thyroid is that symptoms are vague and appear over time. So not only should you follow up on what your current blood test results, you should find the historical ones too and see if there is a long term change. TSH rising each year is an indication that a more serious...
Your doctor should have issued you with a form that they sign and send off. I carry my exemption card around with me and show it whenever asked. The rules only changed recently. Write back and please ignorance and say that you have applied.