I have a strange bruising in the groin area, on the very inside of my right thigh, and occassionally, it hurts when walking or doing something of that nature. That area is tender and one day my bruise seemed to open? There was very, very sensitive tissue or skin ( I'm not sure) in a small spot maybe the size of the head of an eraser or a little bigger. I'm just wondering why this is happening? I have not been doing much physical activity, so I don't know what could be causing this.