PEPSI ISN'T EATING RIGHT SOME DAYS HE EATS ALL HIS FOOD N OTHERS HE JUST PICKS OVER IT.TONIGHT HE POOP WAS DARK BROWN ALMOST BLACK LOOKING,HE'S UP TO DATE WITH ALL HIS SHOTS AND HE HAD A LITTLE COLD A FEW DAYS AGO,HE'S GAINING WEIGHT GOOD THE VET SAID,SHOULD I BE WORRIED ABOUT THIS POOP BEING SO DARK