Thank you for your patience. KC's symptoms are definitely quite concerning, and there are a number of possible causes for her symptoms including anything from an acute gastroenteritis, to a toxicity (hopefully there isn't anything your girl could have gotten in to), to an infectious issue or even an internal organ problem. You will certainly need to continue to keep a close eye on KC over the next few hours, and if she becomes any more painful or listless, you will definitely need to get her seen by your local ER vet tonight.
I wouldn't recommend giving your girl aspirin. It is unlikely to assist with a temperature if she has one (the drug isn't as effective in dogs as it is in humans), and it can also potentially complitcate things by causing side effects. Instead - as your girl may well have a sore abdomen from what you have said - you could try her with a little pepcid. The typical dose for this type of situation is 0.25mg per pound of body weight up to twice daily. You can read more about the use of Pepcid in dogs online here: http://www.petplace.com/article/drug-library/library/over-the-counter/famotidine-pepcid . For now, with hold her food for a couple of hours, then try her with something really bland. For this, cooked, boneless, skinless chicken breast and boiled white rice is ideal and you can feed this for 2 - 3 days.
For now, please keep an eye on her mucus membranes, capillary refill time and respiratory rate tonight 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 seems to be panting or breathing rapidly throughout the night, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
Best of luck with KC and hopefully she just slowly improves this afternoon and this evening. 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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