Yes it is probably herpes. As we age we tend to sit longer so that may be why it is on your tailbone. I am 76 and have had them on and off for 40 years. They start out itchy and pimply . Sometimes just one boil like pimple. Then break open an ooze making them itchier. Don’t spread them by actually rubbing them. Put on acyclovir cream and take oral acyclovir twice a day. Anti itch gels and tea tree oil (don’t get too close to private parts or it will sting) help a lot . If you get them often, which is what happened to me after radiation treatments on my tailbone, ask pcp for prescription for valacyclovir which you take daily as a preventative. Good luck.