Is it bad if your poop is a bright green
Only if it glows in the dark, then you may have been exposed to 4 or more rads of nuclear contamination. Play it safe and send a stool sample to the Los Alamos lab.
That happened to me after I drank 2 large slushies.Did you drink anything like kool-aid, slushies, iced tea, etc.?
It probably isn't a sign of anything. Most likely just something you ate/drank.