Glad to hear you have a firm diagnosis and are " fixed " now James, however medicine is not an exact science and we are not all textbook cases. I am sure your previous doctor did not misdiagnose on purpose and maybe it is lucky it was a year until a new diagnosis. Sometimes patients have to wait much longer, through no fault whatsoever. I hope you continue to be well.
Pleased you got yourself sorted and hope you continue to be well , stick with the Doctor you have confidence in and ask for a second opinion if you're unhappy .