I have water retention on my left shoulder . its not really painful but it snaps and pops and makes movement sort of troublesome . ?

Bursitis?: Sounds like it's either bursitis or a joint effusion, which is fluid inside the joint itself. We recommend anti-inflammatories (if safe for you) and rest. If the fluid persists, your physician may be able to drain if in his/her office.

Arthritis: It sounds like you have a problem . You could have arthritis of the shoulder or tendinitis or capsulitis. You should see an orthopedic surgeon who specializes in shoulders to evaluate your problem.