A previously explained about the causes of neck pain can not miss the emotional state of the person, explained deeply in Articles back pain and emotions.
Mainly two causes of pain. The first is directly related to the tension generated in the muscle which attaches to the cervical vertebrae in the first dorsal and in the paravertebral muscles. This tension generates a deficit of blood circulation, which in turn causes a small decrease in oxygen supply to that area of our body. That little oxygen deficit will cause significant pain, which can produce some difficulty when moving the neck.
The second cause may be accompanied by the first or not. The rotation is carried out by sideways cervical vertebrae, which can cause compression exists one or more spinal nerves.