Question: MRI for fibromyalgia?

I was diagnosed with fibromyalgia 18 months ago. I was diagnosed by a rheumatologist. I had numerous blood test and chest x rays before being diagnosed.
I was just wondering if I should have had a mri as well to rule out anything else. Especially as I had a fall down the stairs around the time I became unwell.
Should I ask my gp about a mri.