Collor Bone

A few months ago, i have realised that my left collor bone appears to be sticking out more than my right. I have never injured my collor bone at all and i have no idea what is causing my left collor bone to be forward than usual. I regulary go to the gym and exercises such as Clean Press and Front Squats irritate my collor bone a lot ( causing it to become sore).
Does anyone have any idea's what is causing it and what i could do to help it :\, Please Help.