preparing for RAI

Hello, I'm into my 3rd week off synthroid in preparation for RAI treatment next week. The hypo symptoms haven't been bad.... yet. Am only experiencing a little brain fog & energy levels a bit draggy at times. I'm scheduled for labs next Monday to check my TSH levels. If those levels have reached 30, I'll be having the one time RAI treatment on Wed. or Thurs. of next week. Was wondering if anyone had any specific advice for me on what to expect after the RAI? I had a total thyroidectomy in November because of suspicious 2 cm mass on the left lobe of my thyroid. The surgeon also removed 13 lymph nodes & one of my parathyroid because she didn't like the appearance of the thyroid. The surgical biopsy revealed a papillary/predominantly follicular variant cancer, that had not metastasized into surrounding lymph nodes, but it was within the vascular system of the thyroid. Prior to my surgery, I had a fine needle biopsy that suggested the mass to be benign, but because of various other issues, we decided to go ahead with surgery. I would very much appreciate any insight from any who have already had the RAI treatment. Thanks