Why are you being treated by a chiro at this point? I strongly suggest you seek the counsel of a spine doctor to see what is going on in there. Have you had an MRI done recently? Chiros can be very useful, but when you have back trauma, it's really important to be properly diagnosed. Improper manipulation could cause irrepairable damage, and nothing is worth that in my opinion.
The indentation is more than likely a soft tissue issue, but you need to know "why" and treat it accordingly.
The fact that your pain is migrating could mean something more serious and you really need to be seen by a spine specialist if possible.
Best wishest to you and please come back and let us know how you are doing. take care. Tammy