Hi,
3 grains of Armour is full replacement hormone. Were you on this dose very long and what did your thryoid hormone levels look like? Armour can cause FT3 levels to rise too high in some people. And there can be variations with batches. My FT3 rose a little after starting LDN but my doctor and I aren't certain if its from the LDN or because FT3 levels tend to rise over time in people on long-term Armour.
From what you're describing your FT3 might be too high. I would stop the LDN until you get your lab results. If your FT4 and FT3 levels are within range, you might want to resume LDN at a lower pace, using it every 3rd day initially and then if you're tolerating this dose, lower it to 1.5 mg every other day. I wouldn't increase this dose any higher without first getting repeat thyroid function tests to make sure your levels are remaining stable.
I think a change in your thyroid hormone levels, most likely a rise in FT3 is causing your symptoms. Thyroid hormone is very potent and even slight changes, like a 0.3 rise in FT3 can cause symptoms of hyperthyroidism. Let me know how your labs turn out. Best, Elaine