I agree with Bronze. I have some of these habits, chewing the inside of my cheeks, I was once a nail biter, teeth clenching/grinding. A lot of these are caused by large amounts of stress that can lead to large amounts of anxiety. We begin to grow so used to these reactions that our minds don't let us know we are doing them. For example, it's like when people say you wont remember what you had for dinner three nights ago because your mind saw no importance for it. Soon it becomes mechanically habitual.