How long ago was the first MRI? If it was recently, I would ask him about the need for a second one. MRIs are very expensive, and uncomfortable for me anyway.
My decision about having tests of any kind, is "How will the results of the test change my treatment plan?" If the results of the test will not change the treatment plan at all, I see no reason to do the test. At this point in my life, I am not really interested in just collecting test results. Whether the disc is bulging or herniated, if epidural injections would still be considered as the treatment, why get another MRI? Does he have other reasons for another MRI?
Would it change the plan? For instance, if the disc is still bulging, but not herniated, would he cancel the epidural injection plan?
If I were you, I would research the epidural shots as used for herniated disc related pain prior to actually having them. There are risks involved with any injection into the spine.
My last comment is to ask if this doctor is an "interventionalist" PM doctor. Are injections and procedures the only kind of treatment he uses for pain?
Some pain management doctors only do this kind of treatment, and do not do non-interventional treatments like oral meds, cognitive therapy, OT, PT, massage, biofeedback, etc. that just require repeated office visits. The cynical side of me wonders if it is because insurance companies reimburse much better for injections and procedures than they do for office visits.
Just things to think about.
I hope it all works out well for you.
Take care, Annette