Friend, in a young dog like Sterling the symptoms that you are describing can be caused by many different medical conditions. It will not be possible for me to pinpoint the exact underlying cause without a hands-on examination and some testing, I am sorry. But, common causes are dietary indiscretion, ingestion of a foreign body, infections, parasites, etc. to name a few causes. To determine the exact underlying cause she will need a hands-on examination by a veterinarian, x-rays, fecal analysis and blood work as an initial screening test. Strongly recommend having her checked in the morning by your family vet. In the meantime, this is what you can do:
1- Do not give things like Pepto Bismol or Imodium. Start her on Pepcid AC (famotidine) 10mg tablet every 12 hours for the next 2-3 days. You can buy Pepcid AC over the counter in any pharmacy.
2- No food or water for 8-12 hours. Need to give her gastrointestinal tract time to rest.
3- After 8-12 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 on this diet for several days then wean into regular diet.
4- Follow up with your family veterinarian for a hands on examination in the morning.
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