This is because of the neck muscles and surrounding muscles which come under stress after prolonged sitting, travelling,and manual exertion.
Next Steps
go to a physiotherapist and take the treatment. Ultrasonic therapy helps in healing of muscle stretched or inflamed,heat therapy increases blood circulation and TENS helps in relieving pain,Exercises will increase the muscle strength and range.Do it for at least 2 weeks.You will get the relief for sure.
Health Tips
for neck..at home-avoid sitting for long, no forward neck bending, no manual exertion, no cold exposure, no travelling,no weight lifting,no table work.