Often we use levothyroxine during severe hypothyroid phases of thyroidits then taper off the medication -- this can be a bumpy ride for many patients, but usually with time, the levels stabilize but this may take several weeks. We usually recheck levels 4-6 weeks after stopping meds to confirm normal. The nausea and dizziness are not typical thyroid symptoms. Would continue to discuss with your doctor to make sure nothing else is going on.
It's been 22 days now were I'm off the meds and still no improvement everytime they do a blood test they only test tsh and FT4 and those come up normal so they tell me I'm fine and send me home I just don't know what to do anymore !