I had a small pimple like bump on my inner thigh. I popped it, a large whitehead came out and some pus. Afterwards i felt this hard little rock like think under my skin. My mom got a sterile needle and dug it out. It looked like a small shell and was hard as a rock. Could not break it at all. Also, this was located near a stretch mark i have. Now it looks like a mini crater and is bleeding. I m kinda freaking out because I do not know what the black pebble is!