Pooping blood, lethargic, puking, not eating
I understand your concern about your dog's symptoms. The presence of blood in the stool, vomiting, lethargy, and loss of appetite are indeed serious signs that could point to various severe conditions, such as gastrointestinal bleeding, infections, or even poisoning.
In the meantime, it's important to keep your dog hydrated. Offer small amounts of water frequently, but refrain from giving any food until you can seek professional help. These symptoms indicate that your dog requires immediate veterinary attention to diagnose the underlying cause and provide the necessary treatment.
I strongly recommend taking your dog to an emergency veterinary clinic as soon as possible. The combination of these symptoms can lead to dehydration and other complications, which can become life-threatening if not addressed promptly.
If you have any further questions, please don't hesitate to ask. Thank you.