Welcome Sarah,

I think it is positive you are at least getting relief when you refrain from sitting at your computer desk. It sounds like there is definitely something going on with that. Figuring out where the problem is will be key. Hopefully your MRI will give some info. Sometimes even simple xray can show compression. I have some compression at C5-6 and osteophytes which was found on xray by an orthopedist. Even though the compression is mild it was causing symptoms with certain positions and activities. The good news? a few adjustments in my routine and identifying what set it off have made a HUGE difference.

take care, I hope you find relief and answers soon
Sending Healing Love,
Littlepaw