Hi Melissa,
TMG is the second most common cause of hyperthryoidism in young women. Multiple nodules are usually always benign. The College of American Pathologists recommends a low-iodine diet to reduce the size of nodules and any associated hyperthyroidism so your plan to add more goitrogens is sound.
Your thyroid levels are only slightly elevated although a FT4 level is much more accuate than the T7, which is a calculation based on the T4 and uptake (measures binding proteins). Most labs don't even run the T7 since it's considered obsolete.
With your labs only being slightly elevated, staying on your 5 mg dose sounds reasonable and if there was any increase, it doesn't seem that more than a 7.5 mg dose would be needed.
People who have thyroidectomies can have problems with infertility if their hypothyroidism isn't properly treated. As you might have noticed from comments on the board, hypothyroidism that requires full replacement hormone is not easy to treat.
The usual protocol with multiple nodules is to repeat the ultrasound in 6-12 months to see if the nodules have changed in size. A reduction in size is always good and suggests benign nodules. An increase in size would be an indication for a repeat FNA. In general, it's better to have labs and imaging tests at a dedicated facility than a doctor's office as the quality assurance guidelines for tests performed in doctor's offices are less stringent.
TU is the obsolete thryoid uptake test, sometimes called a T3 uptake. T7 is just a calculation that we used twenty years ago before tests for measure FT4 were available. The last two tests are thyroid antibody tests. These are always present in Hashimoto's thryoiditis and in 70% of patients with Graves' disease. I'd ask for the TSI result as well since many doctors have trouble interpreting the results.
Best, elaine