How do I know if I have a pilonidal cyst or a herpes sore? What are the differing signs and symptons? I have had a sore at the base of my tailbone for ten plus years now. It frequently gets infected and puss will come out. Sometimes it gets very swollen. When it heals, I have a scar what looks like a mole on the area. The center is soft and tender but the surrounding areas feel tough, like scar tissue. It doesn t really itch. But it does hurt if I lie down on it the wrong way.