Chronic Neck Pain. Could be the reason.

My daughter is 10 years old and she has persistent pain in both sides of her neck for a month now. This seems to be muscular pain to me as she tells me that she feels pain from the inside. I have visited Orthopaedics and they have examined her, according to them, there is nothing to worry about as her neck movements are fine and she has no other symptoms. I still insisted on prescribing X-Ray and that report too came normal. They have prescribed regular pain killers and ointments but it is not effective. I am more than worried as her neck pain is not getting subsidized. She has started complaining about back pain also now. Her blood report came normal and vitamin D level is 35. Have seen 3 doctors until now- Orthopaedic, Pediatrics and ENT specialists. None could help. All of them are just giving pain killers. What could be the reason.