I am sorry that you are having this problem with your dog. In response to your question, if she ate the chocolate on Friday I don't believe this is related to the chocolate or tortilla. The presence of blood suggests that this could be related to ingestion of a foreign body, an infection, or even part of a systemic disease, etc. To determine the exact underlying cause he will need a hands-on examination by a veterinarian, blood work, and x-rays as an initial screening test. Treatment will be based on exam and test results. In the meantime, this is what you can do:
1- Do not give things like Pepto Bismol or Imodium. Start him on Pepcid AC (famotidine) 10mg 1/4 tablet every 12 hours for the next 7-10 days. You can buy Pepcid AC over the counter in any pharmacy.
2- No food or water for 6-8 hours. Need to give his gastrointestinal tract time to rest.
3- After 6-8 hours offer a small amount of water. Wait half hour, if no vomiting, offer a small amount of rice (50%) and boiled boneless chicken or ground beef (50%) 4-6 times a day. Keep him on this diet for several days then wean him into his regular diet.
4- Follow up with your family veterinarian for a hands on examination. If cost is a concern I would look into your local ASPCA or Shelter where they often offer veterinary services at a lower cost.
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