Dark green stool?

Today when I woke up, I had cleared my bowels, 2 times, and it was all normal stool. A little soft, but normal. Then I had the urge to go again around afternoon, and I noticed that I sort of had diarrhea, but it was muddy, dark green color, and it immediately sank to the bottom(I heard somewhere that if stool floats, its good). So I'm a bit concerned, and do you have any suggestions? I'm 16 years old, if that helps in any way.

[Inkling]

It could be that you ate something bad. The last time I had food poisoning, I had dark green diarrhea for a couple of days.

[gnorb]

Green stool is generally nothing to worry about. It means that it went through your colon very quickly (likely, based on your description) or there was extra bile for some reason. (Eat anything super-fatty and out of the ordinary lately?) Could also have been something you ate. Unless green stools suddenly and for no reason become the norm, it's nothing to concern yourself over.

As for floating, actually it's the other way around: if stools float (continuously) then you might have issues with fats not digesting very well. (Occasional floating is fine, normal.) A slowly sinking stool with a semi-soft consistency is well normal. Sinks too fast, there's too much protein. Floats, means there's gas stuck in the stool or fat (at your age, most likely the former.)