The picture is difficult to tell except that your right shoulder is sitting lower. Typically, the shoulder of our dominant arm sits a bit lower than of our non-dominant arm because of increased stiffness of the musculature from it being stronger. Not to mention the human body is naturally slightly asymmetric due to our natural structure of our internal organs, diaphragm, and motor cortex of the brain. As long as their isn't a scoliosis issue (like Odin brought up) or your posture isn't causing pain, just working on your overall posture would be best. Good luck.