Please call your doctor’s office and explain how this is affecting your quality of life. Ask if he/she would be willing to work with you on a dose change with followup tests. You obviously don’t want to spend the next two months feeling miserable.
Twenty years ago, there was an idea that patients could get a “goldilocks” dose of RAI that would destroy just enough tissue to leave them euthyroid. These days, patients get a “fully ablative dose”. So it’s possible you were left with a certain amount of functioning tissue after RAI, and things have since changed.