Thank you very much for your questions. You are very right that most of the neck problems in your age group is likely due to bad posture (humans are not designed to stare at laptops/ handphones for prolonged period of time).
However, if you feel that the symptoms are worsening and not resolving over 6 months, I do suggest you get a proper check up by a doctor or Orthopaedic surgeon.
We will do a MRI scan to ensure that you don't suffer from anything more sinister such as a slipped disc in the neck. We can also advise you about proper postures and proper exercises that you could do to improve your symptoms.
Hope it clarifies some of your doubts.
Cheers!
Dr. Henry Chan