I believe she may be lethargic (extra tired) because she does not feel well. The big question is: What is making her vomit? This can be caused by many different medical conditions. Common causes are ingestion of a foreign body, infections, kidney or liver disease, etc. to name a few causes. Unfortunately, we are very limited as to what you can do at home, I am sorry. In this case, Bella will need a hands-on examination with your family veterinarian, x-rays, and blood work as an initial screening test. Treatment will be based on exam and test results. Strongly recommend having her checked in the morning. If cost is a concerned I would look into your local ASPCA or Shelter where they often offer veterinary services at a lower cost. 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 1/4 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 3-4 hours. Need to give her gastrointestinal tract time to rest.
3- After 3-4 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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