My right clavicle is bigger than my left clavicle. i have bad posture, right handed and use mouse all day. however at the end of my right claivicle (near center of chest) bone is bigger. no nodes felt?

Likely normal: This is likely a normal variant. Your bones should not "hypertrophy" or get bigger from overuse. Bad posture and sitting in an office chair is a common complaint among my patients and may lead to musculoskeletal discomfort. I recommend getting out of your chair at least once hourly if not more and performing basic stretching exercises.

?sternoclavicular jt: The inner part of the clavicle forms a joint with the sternum (chest). This is called the sterno-clavicular joint and gets often inflamed in certain activities making it swell up and become prominent. The joint may not cause much pain and usually rest and some anti-inflammatory medications may clear it. Cortisone injection often help the pain and swelling if needed. Need an x-ray and medical check