Question
Hi,
I am 23 and am having cracking when i roll my right shoulder. it is not happening on the left, and i think it may be caused by the heavy bag that i carry to work and school. it cracks a LOT when i rotate the shoulder, but the cracking is in the back near my  neck--not in my arm. PLEASE HELP!!

Answer
It sounds as if the joint, in taking some extra stress from the bag, has some inflammation.  You might want to switch shoulders for one.  An evaluation by a good chiropractor could reveal if there are any mechanical issues, and when treated, a proper rehab program should be set up.