What type of pellets do you feed her? And how many pellets do you feed her once?
I guess the red worms are the reason for black pop. I don't know what kind of worms are these ones, but I know for sure that when it comes to bloodworms they should be fed only once a week, one feeding made from 2-3 bloodworms, as a treat. In the case of red worms... I have no idea.... Maybe some other person here can tell you more.
Anyway, I suggest to fast her for a day. No pellet, no worm. And we'll see after this how she is doing. Do you usually fast her one day per week?