Hi,,i m 22 yrs old..for last 2 yeras i hav pain and some sort of stiffness in my neck (back portion)..it becomes more whenever i m under stress or studying regularly..whenever i open my jaw or move it side to side i feel some sensation like some crystal is breaking in my jaws..i feel continuous stiffness in my jaws and upper portion of my back..i hav consulted few doctors but they said i m fine i hav to change my posture of sleeping and studying..please help me..