Sprain or lack of calcium? (pain, arm, time)

[Croye22]

My arm - every time I move my left arm from a resting position, I hear a small to moderate popping sound. Doesn't matter what I am doing, it will make a popping sound and I don't know why. Only thing I can remember is when I was 15, I had a sharp pain on my shoulder, but it resided and never came back.