Talk to Orthopedic Surgeon on Popping Sound In Ribs

I had some physical impact on my left side ribs a couple weeks ago. Initially I had severe pain which was managed by pain killers and an orthopedic doctor said that in x-ray all of my ribs seem to be fine.

Now I have light pain on the lowest ribs and in addition to that there is some popping sound at center of the middle rib (maybe costochondral separation) whenever I change side or get up after laying.

Can someone please tell me what kind of specialist I should see for further diagnosis?

Thanks,