hi...a few things came to mind reading your message.
firstly, magnesium needs calcium to absorb (2x magnesium amt). check in with dr to make sure okay. calcium doesn't hurt us if we have adequate magnesium.
the leg thing could be an accumulation of mucin- a substance that clogs circulation ,etc. and comes from hypothyroid. google it and ask your dr about it.
also, b complex is important as well as selenium. you might want to look into standard process organ meats -
they've really helped me with thyroid issues- it activates the hypothalamus and pituitary.