That sucks!!
Now for some practical advice. Getting some good sleep is absolutely essential for you to be able to get over this as quick as possible. So using meds to help sleep is a good thing. You can try some strong over the counter meds first (if you know your body tolerates them). If those don't work, you may well need a prescription med to help you get over it. Also, many of my patients that have similar MRIs to what you're describing do really well sleeping in a recliner. It's sitting, but because you tip backward, it can take some pressure off your back but would keep you upright enough to help with the breathing bit.
Good luck. Get better soon!!
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