When I go through frightening urges like this I ask myself questions like:

"Why do I want to attack [particular spot you have the urge for, in this case:] my mouth?"
"What do I believe I have done to deserve this?"
"Do I really believe I deserve this?"
"Why?"

Sometimes I found that I wanted to attack certain body parts because in my mind they had a symbolic attachment to something I was upset about. I don't know if this is the case for everyone... For example I get the urge to harm my wrists (even though I never have) when I feel I am trapped or enslaved in some way. I have wanted to harm my throat when I have actually felt like I have used my words wrong, or no one is hearing me correctly.

The thing I realized is that I can follow through and give myself more pain, or I can find something to do in small baby steps that would give myself a slightly better feeling than what I have. Now when I get the urge to hurt my wrists I imagine the line turning into flowers growing on my arm and it's calming. Or I imagine a beautiful necklace around my neck.

I don't know what this is for you, sweet-heart... Only you can find out, and even if you never figure it out, you can do something to replace that urge.

So also ask yourself "What small thing can I do to feel better?", you don't have to achieve happiness, just better than where you are now.

Good luck, hon. I'm cheering for you.