This happened to my little guy very shortly after I brought him home. I felt so terrible, but I just took him to my vet so I don't have any "household remedy" ideas. He got some sort of medicine at the vet and and an enema
He was all better after that, but since he was having trouble going, his bottom was sore for a while...poor guy. But to answer you question, I really don't have an answer.... If you feel like you need to, can't you take him to another vet in your area today?? Good luck!