While I am not an expert by any means, I do know feces that are abnormal in color should be examined by a vet to check for parasites and/or other diseases. Red feces could mean that something is bleeding in the cloaca or end of the GI tract.
+1 for both the above. Bloody stool has to be from the end of the gi tract. Could be from many many issues. Vet trip is gonna be the best bet. Good luck fingers crossed.