Hiya,
I was on diclofenac and co-dydramol to start with and was also put on diazapam to help me 'relax' in the evening. Once these started to have no effect I was put on Tramadol and gabapentin along with the diclofenac and diazapam (it cost me a bloody fortune). Taking that cocktail of drugs was only way I could function and get through each day, gabapentin was a god send as it acted like a nerve block which meant I didn't permanently have sciatic pain.
My life was basically on hold for 15 months and in that time I don't think I lived I just existed, but it wasn't just my life it affected it was my oh's aswell, i've got to say it is one of the worse things I have ever been through..it was hell.
Diclofenac can cause problems with your stomach so maybe ask the dr if there is anything else you can take, and also ask if they can rush through your mri.
Hopefully you will get sorted a lot sooner than I did.
Take it easy
Nay x