Cortisone shot in shoulder

I'm 43 years old and in relatively good health.  I've been having shoulder pain in my left shoulder for a few years that has gotten progressively worse.  It "snaps" and almost feels like it "slides", I have pain when I cross my left arm in front of my body or behind my body.  The pain is in the front of the shoulder, right below where the collar bone ends.  I saw an ortho doctor yesterday and he said I may have frozen shoulder and gave me a cortisone shot.  He said if the pain does not alleviate within a week, to call him back and we'll schedule an MRI.  Of course today my shoulder is hurting because of the shot yesterday (I had a cortisone shot in my hip a few years ago for snapping hip and I remember it hurting for about a day after and then it eased up), but I still feel that "catching" sensation in the joint.  My question is should I still be feeling that pop and catch feeling with the pain, will that diminish as the soreness from the shot eases or should the original pain be easing up already.  I remember with my hip the soreness from the shot and it was difficult to walk the next day, but the actual joint pain wasn't as bad.  Thanks