Every ha person desperately hopes reassurance and doc visits and med testing will be the THING that gets them on their healing path. This whole forum has hundreds/thousands of posts saying things like, "if I get this test or that test, I will be able to move on." Or "I need X test then I will know it is anxiety" or "I promised myself that if X test is normal, I will believe it and THEN I will be assured". There are many variations on that theme around here. I read such things everyday. AND it is all poppycock. So you can certainly go and get that MRI, but, unfortunately, it will not fix what ails you. As another member here, floridaguy, was apt to say, "Lasting solace will never be found in an MRI tube, CTscan, with an EKG or EMG, or with another round of blood tests" Unless one abandons the reactive behaviors associated with anxiety and replaced by proactive ones, the vicious anxiety will not be broken. I am not saying it is easy, not by a long shot, but it is worth it.
good luck and be well.