Thank you for your patience. Mitzi's symptoms tonight are very concerning and you will definitely need to continue to keep a very close eye on her for the next few hours if you can. The vomiting and blood in her vomit could definitely be due to the vaccination she had today (a vaccination reaction potentially), or she could have something else entirely going on here such as an infectious gastroenteritis, or a primary GI or organ issue (given you don't know her history). Hopefully you can convince her to drink water at the moment, and hopefully she is able to keep water down. If not, the concern is that she could quickly become dehydrated - so do get her down to your local ER vet if she either won't drink water or can't keep water down.
Because she is vomiting blood, it will be important for you to keep an eye on your girl's mucus membranes, capillary refill time and respiratory rate as follows (do be careful that your girl doesn't try to bite you):
Mucus membranes - flip her lip and look at the color of her gums. They should maintain a nice salmon pink color. Get her to the emergency Vet if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on her gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.
Respiratory Rate - if she is continuously panting or open mouth breathing at all tonight, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
If any of these parameters aren't right, or if she continues to vomit, please do get her seen this evening. For now, you can with hold her food until the morning. From then, try her with some cooked, boneless skinless chicken breast and boiled white rice for a few days. Hopefully this vomiting settles in the next hour or two. I hope all of the above makes sense? If you have more questions or if I can help in any other way, please do not hesitate to ask! If you would like to accept my answer, please press RATE OUR CONVERSATION (I am not compensated in any other way). Bonuses are always welcome. Thanks! I hope to work with you again soon!
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