Something's wrong

Took Ronnie out for a walk, on a leash together with Ley on his little green tricycle. It is a fine evening, where nobody is burning anything, the air is fresh and little cool, a perfect evening for this hot and humid country.
I noticed some quite worrying about Ronnie. Its poo is fresh red in color and soft and juicy like ketchup. I am not sure what's wrong with him. Could be he has ate something bad or he has some kind of hidden disease? Or maybe he had a fall somewhere and end up with internal injuries?
I will monitor the condition tomorrow and if the problem persist, I might need to consult a vet soon.