According to your sign and symptom you are suffering from some muscle spasm of the neck.
For treatment -
you should take some muscle relaxation
Tablet like Flexon Mr two times per day after food
with capsule Pentop D once time per day and multivitamin with
calcium and
apply any painkiller Gel .
Next Steps
you should do some physiotherapy and exercise of the neck to make strength and flexibility of neck muscle.
Health Tips
Keep positive attitude to fight any disease and any problem of your life.