You have to give it time. I had my RAI in Dec ’08, and it took a couple of months before I felt better and had the strength to even step up on a curb!
After a month I had an appt with my endo and then 5 times after that, I had to go back to her every 2 weeks for blood work and a weigh in, and they checked my blood pressure and felt my neck.
It wasn’t until mid-April of this year that I started on Synthroid – once my levels were "hypo".
I don’t have to go back to my endo for 4-6 months now, but in a month, I have to do some bloodwork so they can check my TSH levels again – since I was 6.22 last week and then got my Synthroid dosage upped from 125 mcg to 150 mcg.