Friend, the history and symptoms you are describing are consistent with a urinary tract infection. You see, the increase in frequency to urinate is because she has an infection that is causing irritation (inflammation) of the urethra (tube connecting bladder to vagina). When the urethra is inflamed it gives the feeling of having to urinate, this is why she is going more frequent; the increase in frequency does not allow the bladder to accumulate enough urine and only produces a small amount of urine every attempt. Other possible causes could be bladder stones.
As far as the vomiting, this can be caused by many different medical conditions. It will be difficult for me to determine the exact underlying cause without a hands on examination and some testing. But, common causes are: A simple gastritis, dietary indiscretion, intestinal parasites, ingestion of a foreign body, infections or even part of a systemic disease etc. to name a few causes.
In this case, we are somewhat limited as to what you can do at home. I would highly recommend having her checked by family vet for a hands on examination, urinalysis, xrays and blood work as initial screening test. Once your vet confirms she has a urinary tract infection they will start her on oral antibiotics. In the meantime this is what you can do for the vomiting:
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- Change her diet to 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.
3- Follow up with your family veterinarian for a hands on examination as described above. If cost is a concern look into your local ASPCA or Shelter where they often offer veterinary services at a lower cost.
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