is your pain radiates to your arms?
when pain gets aggravated/relived?
is there any relation with stress/medication due to other reason/menstruation?
pain in other body part is there or not?
these are the questions to know your problem properly.
sometimes postural problem may lead to neck pain
but as your pain disturbing you for 1month few investigations like x-ray of cervical spine
you can take common analgesics ,antiinflammatory & muscle relaxant
& use a cervical bracing
hope it will help you.
if persist then contact an orthopedic doctor.