Maybe a standing MRI? That may show if standing & gravity is a factor..
Bulging disks alone may or may not cause pain..it all depends on the details..
Sometimes MRI reports might say mild , moderate, severe, and if something is impinging on a nerve or the spinal cord..

We do have a Spinal forum where more information on spine care can be found.
http://www.neurotalk.org/forum22/


Have you had any phys therapy?
Perhaps low level laser, IF stim or acupuncture might be helpful.