are you sure that it's poo....
cause it sounds more like a regurgitation to me
here is what you should do if it's a regurgitation
1) Remove halfly digested pinky (it should smell real bad..much worse than the poop)
2) Leave it there for at least 7-10 days for the acid in the stomach to rebuild.
3) During those 7-10 days no handling, no nothing. You can change the water, but remember try not to distrub it
4) Try to feed a smaller mouse than before after the 7-10 days.
5) After it eats and no regurgitation occurs wait another 4-5 days and offer it food again. Repeat 5 again at least one more time before handling.
6) You can start handling the snake once it has keep in it's meal at least 3 times.
7) Have fun!
Good Luck and Happy Herping!!!