Man, I had the worse case of the shits in my life after my wife and I and a couple of friends went to the CMG in my town. I had 2 burritos and 12 hours later I was doubled up with gas pains and shittin' like a shark. I'll never eat there again.
That's a shame you won't eat there again, because they probably have very few customers that eat two burritos in one setting. And they are potentially pretty high in fiber--which if you aren't used to it might not be terribly pleasant.