No question is too yucky when you need to find answers.
Bowel incontinence can be a problem with MS -- the sudden urge to defecate, and inability to control it until you get to a toilet. It's important that you tell your doctor that you're experiencing it. I don't know if there are meds to control it, but he can help you develop a "bowel program" to reduce the times it happens.
I find that I have to be VERY careful to avoid any food that might have MSG in it. That never used to bother me, but now it does. Often buffets will "spice" their food with msg -- Accent is a common brand name -- to enhance the flavors of foods that sit around for awhile. So it may be that you've developed a sensitivity to that, like I did. I love chinese food -- and don't dare eat at a chinese restaurant unless I'm CERTAIN that they don't use msg...and the front-line waitresses don't always know. You might ask if msg is used at the restaurant where you were eating, and if so, you might avoide that. And I am careful to "work" my bowel program, especially if I'm going to be out and away from places where I know there is quick access to a bathroom.
IBS -- irritable bowel syndrome -- is a sort of generic name for bowel difficulties, which can include both constipation and diarrhea. Often they'll alternate -- you'll be constipated, then suddenly have to defecate, and not be able to control it.
The intestine is a muscle of sorts. Think of a snake, moving through the grass -- a sort of undulating motion, expanding and contracting along the length of the snake. That's how the intestine looks as it passes food from the stomach down to the exit point. If the signals from the brain are imperfect (which they often are, in folks with IBS, and/or MS, and/or several other disorders), then the contractions might stop, or slow down dramatically, and waste products will "ferment" in there for awhile. Then move a bit again..then stop..then move...then stop...
and if you don't have a bowel movement daily, or every-other-day (or every third day) ....EVENTUALLY it'll pass to the outside -- and that's what happens: you'll get a sudden urge to defecate, race to the bathroom, and if you're REAL lucky, you'll have made it...but often you won't.
So my bowel program is generally this: I try to have a bowel movement at least every other day. If I can't "perform" naturally, then I use a pure glycerine suppository (non addicting, non dependent) to loosen the fecal matter. I try to visit the bathroom *at the same time* every day. I try to eat something in the morning (hard for me; nothing much is appetizing before 10 a.m.!) because that's when the body most naturally performs the task of eliminating waste. If I know I'm going out, I'll *be sure* to use the suppository to clean myself out as much as possible...and as already noted, avoid places where I suspect they might use msg.
(Note: the msg is just MY trigger. You might find something else. Often fatty foods can trigger this, rich foods. Look at the triggers they talk about with IBS and see if one of them is a trigger for you..then you need to avoid that, especially when eating out.)
I hope you're feeling better today.
...I am not a doctor, nor health professional, and don't pretend to be one, here.....