Is biting your lips and inside of cheeks to the point of pain but not being able to stop a sign of something?

Could be: This sounds serious, if you're biting yourself to the point of pain and not able to stop. It's a sign of something, but i don't really know what without talking with you. Please talk with your your doctor, or consult a mental health professional (psychiatrist, psychologist, or other therapist.) once more is understood about you, any help needed can be offered.

It Can Be: Cheek and lip biting is a very common habit, just like fingernail biting or hair-twirling. It's often a sign of stress and underlying disquiet. This type of clenching behavior often occurs primarily during sleep. In some forms of mental illness, such habits can become exaggerated. In either case, if you're having pain and can't stop, you should get help. It's usually much easier than you think.