I am glad to hear it is gone, but my brain is racing as to what might have caused it.
I am a bodywork, I do a type of osteopathic bodywork mostly from the work of a French osteopath named Jean-Pierre Barral.
I work on organs and blood vessels and nerves and the cranium and its contents and bones and joints capsules and more.
bones and muscles will go to great lengths to accommodate important structures like organs, so I almost wonder if your thyroid went into a temporary strain pattern and the spine curved to try to take pressure off of it......or something like that.....???????
I had a client several years ago get hypothyroid symptoms after a chiropracter gave her a bad neck adjustment. working on her thyroid arteries fixed the problem and freed up her neck......