Hi there .. Neck pain could be because of bad postures leading to muscle strain or cervical spondylosis or if using hard mattress with hard pillow.. use mattress which your comfortable in n sleep without pillow or use soft pillow. Do regular exercises lik neck rotation exercises. Al these help to strengthen your neck muscles. Avoid being in one posture for long time, keep changing postures. You can use gels containing diclofenac for local application, hot fomentation, tablet diclofenac/aceclofenac.. do relaxation exercises. Better to consult orthopedician once..