Tailbone pain is not necessarily sciatica, though compensating for the tailbone can aggravate sciatica.
I originally hurt my tailbone on a bad bike seat. For a few years after that, I was often quite uncomfortable. Ibuprofen helped but you can't take it indefinitely. It finally got better but there were always uncomfortable chairs for me.
After the birth of my first child, it got very bad again. This time I was lucky and had private health insurance so I was able to see a chiropractor cheaply. Actually, I saw 2 - one in Taunton and one in Exeter. Both used a combination of chiro, acupuncture, osteopathy and physio.
I loved my chiropractor!