I would not expect that such symptoms would occur in such a short time after switching back to Naturethroid. As Barb mentioned, there has been a recall, so anything still available I would expect to be okay. I am again surprised that you would have those FT4 and FT3 results from taking only one grain of Naturethroid. I would go back to what worked, and give it some time to have full effect.
Your ferritin is a bit lower than recommended (100 min.). B12 and D are okay.
Looking at your thyroid tests, your FT3 of 3.3 is is at 55% of its range, but your FT4 is only at 25% of its range. I am really surprised by your levels, with those small doses of thyroid med. I think if it were me I would fall back on your statement: "I was on Naturethroid for about six years and did great. Switched to WP Thyroid without a problem and then switched back to Naturethroid after the shortage in 6/19." What was your dose of NatureThroid and what was the dose of WP Thyroid, and the dose of NatureThroid after you switched back?
Why not consider going back to what worked for you: the NatureThroid at the prior dose? Also, if you have test results from the time you were originally on NatureThroid, please post them, with ranges.
Regardless of the med you take, for which there may be some variation in results, the only thing that should matter is that your FT4 and FT3 levels are high enough to relieve hypothyroid symptoms. Before commenting on your test results, we need to know if you took your thyroid med in the morning before the blood draw. Also, have you been tested for Vitamin D, B12 and ferritin? If so, please post those results.
Also, it is not clear how much T4 and T3 you are currently taking. Please clarify.
I was started on NatureThroid at the end of April and other than the fact that my endo won't give me a high enough dosage, I'm not having any trouble with it. I do have horrible muscle cramps, but I've had those for a while now. Cramps can be symptom of hypothyroidism, but they can also be symptoms of other things, such as Magnesium or Potassium deficiency. Your other symptoms (hair loss, joint pain and fatigue) are pretty typical hypo symptoms.
If you can post your actual thyroid hormone levels, perhaps we can help you sort out the problems. Be sure to post reference ranges with any lab results, as ranges vary from lab to lab and have to come from your own report(s).