Sick Princess

Well the Princess is sick...for the past two days her tummy has been rumbling and she's had a terrible case of gas (for her this is not the norm). She's eating, but not as much as normal and drinking water just fine. A few minutes ago she had a rut row in the floor and I got the first look at a stool sample and freaked. Very very dark almost black and not firm. I can't get in to see the Doctor until the morning and they pretty much told me that since she's still active and eating and drinking that it's probably just an upset tummy and to stop freaking out. But I'm still worried about her, she's never sick and the only day to day problem she ever has is a stuffy nose this time of year. I've got the DH outside now mowing the lawn and going over it with a fine tooth comb to see if he can find anything she's got a hold off, I've just bleached and washed her bowl (plastic but I'll buy stainless steel in the morning) in water that I've heated to boiling. Of course I've taken up her Iams and just put down a small amount of water (she drinks bottled water btw). Can anyone think of anything else I can do tonight?