Hi,
l would say you need to look at adrenal support, with hypothyroidism it is a good idea to look into suppliments for the adrenals as a matter of course, and in your case you have had major surgery too.
A good starting point would be, vitamin C, Himalayan salt and Nutri Adrenal, or if your blood pressure is ok Nutri Adrenal Extra.
Have you had your B12 levels checked too?
L/diva x