FYI - this is Herpes Zoster. It's a leftover of the chicken pox virus that stays dormant in the spine. It can come back during periods of low immunity. It often comes back during periods of high stress. It's horrible.
Interestingly, I developed mine right after I had the first chiropratic adjustment in 15 years. I find that very odd. Herpes in the spine, adjustment, and BOOM.
But I know that is just a coincidence, but it was odd.