That's how it seems to be with SCI, you go along at a certain level for awhile and think there might not be setbacks, and then something happens that makes you realize how unpredictable the whole experience is. You think you can't cope with additional issues, but somehow you find the strength when that's what's on your plate. I hope your MRI won't show anything major going on, but if it does just be sure you have the best medical care available, and think in the long term - SCI doesn't usually progress or regress in a linear fashion, and there's no way to predict which pathways it will take. The psychological uncertainty is very hard, no doubt about it.