This is the same thing I have with IBS but at other times have small pellet like BM with a few larger. Think its all a part of the problem. I seem to become constipated vy easily and am now on stool softener which helps, or Prune Juice may do the trick , both work for me.
PJ
That can be very common actually.
If you have persistant abdominal pain..be sure to check with a gastronentologist.
Best 2 you