Hello, my name is***** and I have over 20 years of experience as a veterinarian. I understand that you are concerned with the amount of stomach gurgling and churning with your girl today, even though she seems otherwise normal.
The noises that you are hearing are the result of ingesta moving through the gastrointestinal tract and gas bubbles. In most cases they are completely normal and seem to cause the kitty no distress. But in cases where the cat acts uncomfortable it is likely that the they is experiencing some reflux or abnormal motility, or painful intestinal spasms that are more than the usual. In severe cases this can be linked to pancreatitis which is a painful inflammation of the pancreas leading to increased enzyme leakage.
Possible causes for this an increase in noises include a change in diet, dietary sensitivities or allergies, or eating things that she should not have like too many fatty table scraps or garbage, bones etc.
If she wasn't feeling well then metabolic organ failures (kidney or liver disease), Addison's disease (hypoadrenocortisim), pancreatitis, inflammatory bowel disease or even infiltrative cancers would be other possible causes.
Has she been given anything different to eat or has she gotten into anything that you know of that may have started all of this?
At this point because she seems otherwise normal I would not recommend anything other than watchful waiting.
If she seems to have an upset stomach later today (not eating normally or retching) to try and settle her stomach you can give either:
1) Pepcid ac (famotidine) at a dose of one quarter of a 10mg tablet per 5 to 10 pounds of body weight every 12 hours
2) Prilosec (omeprazole) at a dose of one quarter of a 10mg tablet per 5 to 10 pounds of body weight every 24 hours
These are acid reducers and may help her feel less nauseous and hopefully stop the stomach churning and settle her stomach. They are quite safe and can be used for several days if necessary.
If she seems to feel better then offer a bland diet of 2/3 boiled, minced, white skinless chicken or boiled, and 1/3 boiled, white rice mixed with some low salt chicken broth to make it easy to lap up and swallow and get additional fluids into her. If she refuses that, you can offer a little meat baby food. If she refuses both then don't push it, she needs hands on veterinary care as soon as possible.
But if things go well and she does eat the bland diet and doesn't vomit feed her the bland diet for 3 to 4 days then slowly start to mix back in her regular food, a little more at each meal. It should take about 5 to 7 days to slowly convert her back to her regular diet.
If her stomach upset continues even with the acid reducers, she runs a fever (more than 103F rectally), or has a lower than normal temperature (less than 99F), has a tense painful belly, or if she refuses to eat even after the acid reducer is given she should see a veterinarian for an examination, diagnostics, injectable anti-nausea drugs, intravenous fluids and supportive care.
But at this point because she seems so normal otherwise I wouldn't change things yet.
Please let me know if you have any further questions.