Stop biting your nails!

[Bones]

I think there's a large population of those who pace when on the telephone. It's commonly depicted in movies too. I wager it has something to do with our need to animate our point. Talking with your hands doesn't work as well when the person can't see you, so the mind amplifies that. I'm probably way off base... It's just a theory. XD

Chewing yourself to hell doesn't sound fun... You should find something to counter that desire. One of my friends used to chew her nails down until they hurt. Her boyfriend was like "fuck it, that's enough" and he would make her wear fake nails all of the time. They broke up and she chews them down again because she's a bad learner. XD But for that time while she was wearing the fake nails, they deterred her from chewing her nails. Not exactly a change of behavior in her case, but if implemented correctly, a variation could be.