I have an issue with an ingrown hair that has progressed into a painless, aparently blood-filled sore with a thin scab over the surface. This has been something I have observed for the past month, thinking it was just a normal ingrown hair. I am, however, moreven concerned as it has persisted. The skin on and around the sore is red and very dry. I once pierced the sore, thinking it was a pimple or boil, and was met with a dark grey pus and lots of blood. Any idea what this could be? And should I get in touch with my doctor?