Having a "perfect posture" ? there is no such a thing !
We are designed to move our body is amazing balanced machine created to be flexible and active to allow us to do run, climb, roll, bend and extend, lift, pull and push and many more
However as with everything there need to be a balance and we shouldn't saty in one position in one time.
Looking at this graffic some of us need to wonder how many hours a day do I spent in this position - studying, typing at work, watching or playing games on tablet ect.
Lack of frequent movement and prolonged flexion with additional head weight which is no longer here supported by thoracic spine but its just supported by muscles and other soft tissues can lead to mechanical neck and shoulder pain, headaches, nausea, posture disorders and restriction of movements even nerve irritation symptoms like pins and needles or numbness.
So stay active, do exercises and keep changing positions!
If you feel you need some more help to manage your pain please get in touch