Had this happen to me this morning. Had a regular poop, eve a little on the constipated side. Then I'm almost through my breakfast when I suddenly have to to again and this time it comes all out at once and it's flaky-looking pieces and a little water and a bit of burning. I think, though, that's all I'm going to do today (hopefully).
What is tricky is adjusting medicine for this phenomenon. I mean, my Welchol and calcium together can cause that first bout of constipation, but I can't very well give them up lest I have actual diarrhea after the first movement. How annoying is that?