Hi, I am a 20 year old male , 6 foot 180 pounds, physically active, social smoker. About three months I noticed a bump on my right clavicle , approx 5 inches to the right of the throat area, and it is mobile in every direction, painless, and feels like hard rubber under my skin. It is above the bone and under the skin, not deep. I wanted to know if it is something to worry about?