First, I agree with Pierro, go to the ER if you feel you are going to hurt yourself.

When I've had such feelings I found just being in the room with a safe person helps. I've found talking to people who haven't ever felt like that does no good. They can't comprehend how it feels. I would get the number of a crisis hotline and keep it close at hand. And if you can get in to see your counselor would even be better. Stay safe.