I understand your concerns about MRIs; however, may I suggests that if the pain is persistent that you may want to rule out any possibilities of a problem. If I were in your position the costs is rather moot when you may or may not have something serious going on. I've found that when I ignore things it tends to eat away my energies in the background.
Unfortunately, MRIs and CT scans are only tools we have for now for looking inside the head. When I was looking into the brain parasite issue (not saying you have this), it was advisable to have both scans done because something may show up on one scan and not the other. The other nice thing about having them is that they're tools for comparison. I also highly recommend that you obtain a copy of them for yourself as a future reference.