Hi there... You don't necessarily need to be seen by an endo, as not all endos are good thyroid doctors. The biggest thing you need is to have your doctor start checking the actual thyroid hormones, Free T4 and Free T3, instead of just TSH, which is actually a pituitary hormone, not a thyroid hormone.
You also should ask to be tested for thyroid antibodies to determine if you have Hashimoto's Thyroiditis, which is the most common cause of hypothyroidism. The antibody tests you need are Thyroid Peroxidase Antibodies (TPOab) and Thyroglobulin Antibodies (TgAb)... You need them both, since they are both markers for Hashimoto's; some of us have one or the other, some have them both.
Hashimoto's is an autoimmune condition in which the body has determined that the thyroid is foreign and produces antibodies to destroy it. The disease is progressive, in that the antibodies continue to destroy thyroid tissue until there is no longer any healthy tissue... ultimately, the thyroid will produce nothing on its own and you will be completely dependent on replacement hormones. This means that your dosage will, most likely, have to be increased, periodically, over time...
Nodules are very common with Hashimoto's and are, typically, nothing to be concerned about, unless they have unusual characteristics or are very large. Yours is very small and apparently, there were no unusual characteristics of concern.
Actual Reference Ranges
T4,Free, Direct 1.13 .82 - 1.77
TSH 3.5 .450 - 4.5
ALT (SGPT) 44 0-44
Thyroid Peroxidase TPO Ab 10 0 -34
Triiodothyronine, Free, Serum 3.2 2-4.4
For what it is worth, my TSH was "only" 4 when I was finally diagnosed - I was very sick at this point. I was over 3 for sure starting 2 yrs prior, the same time as certain odd symptoms started which I assumed were "just aging".
I also did not have good experiences with Endo's, and I do not take levo (NDT in my case) but I think you may not want to wait so long for labs, just in case you need an increase. My understanding is 6 weeks is a good time frame, but ask around.
Good luck, Kel