3 years ago a 10 kg weighted sound box fell into my sisters head , at that time we consulted one doctor and told no problem with the x-ray.after 6 months from that she is having heavy pain . Until now also she is having deadly pain . She is 25 having thyroid by birth itself.she is now using neck collar.PLEASE REPLY what it will be ?

Nobody can diagnose something like that online... they NEED to see a doctor who actually can.