Tg is 102 4 months post RAI

I just saw my ENT the other day and got my latest labs.

My Tg is going down, but it is still 102 4 months after RAI. It started out around 1500.

My TSH is 1.2 and not quite low enough as well.

Doc said that if my Tg doesn't come down significantly he may want me to have another RAI.

Is it normal or usual for ones Thyroglobulin level to be 100+ 4 months out of RAI?

I'm starting to get concerned. My WBS after RAI only showed uptake in the thyroid area, so I pretty much thought I was good to go.