Why do I do this to myself?!

I have recently started picking incessantly and obsessively. My left heel is completely raw, I've peeled of multiple layers of skin and my entire heel is exposed and its very painful to walk. I'm limping these days.
I also pick my lips until my thumb and finger is covered in blood from digging into my lips. This is awful, I don't know why I do this to myself but I look nuts and feel nuts...anyone else feel kind of taken over by this?