Glad it went well!
When I had my MRI (before they even suspected Crohn's or another IBD) they didn't seem to think I would need Depends or anything similar. It was probably the worst test I have had to date! 45 minutes in the MRI machine and I was in excruciating pain the entire time, as I was in desperate need to GO! Mine was more for bladder issues, and they told me to half fill my bladder... the problem was that something (my TI) was connected to my bladder, and constantly pushing on it.. so a "half full" bladder was in fact TOO full... ouch.
In the end, everyone is right! they see these things everyday, it is their job! They were very kind with me, as they knew I was in pain... kept telling me how much long I had left, and as soon as that machine was done let me rush to the washroom!
Good news that everything went well for you!!!