I'm sorry you are going through so many health issues and I hope the surgery gives you your life back regarding the constipation problems you are having. Best of luck with that and I hope all goes well.
My husband, with MS, does have severe constipation. The pain medication he's on though, makes it worse unfortunately, and he does have to use laxatives and stool softeners on a regular basis just to be able to go (doctor recommended). He does have the state of urgency you are describing, no warning, just boom it hits and off to the bathroom he goes.
A good site to start with regarding MS symptoms is the National MS Society website at www.nmss.org
Both fibro and migraine sufferers can have symptoms similar to MS. Both can have issues with dizziness, pain, blurred vision, light sensitivity, and congnitive problems. To make matters harder, people with migraines can indeed have lesions show up on brain scans.
You talked about burning pain? Where does this occur on your body and is it only at night? Do you have any other symptoms that you didn't mention?
I do wish you luck with your surgery and your search for answers. Feel free to ask anymore questions you may have, we'll try to help.
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