Recently I have discovered a lump on the top of my head towards the back more. This was never there before, it causes no discomfort or itching and it seems to be staying the same size and it's hard as a rock basically. Interestingly enough my wife has also developed a similar lump with all the same attributes on her head in a different spot. I'm wondering if anyone else has had something similar to this or possibly know's what this is? Thanks.