Brief Answer:
Stomach FLu Likely, UTI also possibility

Detailed Answer:
Thank you for asking

I read your question and i understand your concern. Fever, loss of appetite, nauseating feeling with a few episodes of vomiting, dark colored urine are all pointing towards an acute infective process likely involving gastrointestinal tract. Viral gastroenteritis also called stomach flu. presents like that but i would have been more sure if you had mentioned bowel habits as such symptoms are always accompanied by a watery diarrhea. If so then all you need is wait and see, continue oral fluids, BRAT diet ( banana Rice Applesauce Toast) and rest. Using advil has delayed the healing as already upset tummy is further upset by advil and even tylenol and should not be used.

Apart from stomach flu other foci of infections need also to be ruled out as dark urine may point towards a urinary tract infection as well but that usually followed by increased frequency, burning micturition or rigors and chills with fever.

I would suggest get a urine routine exam and other baseline work up to rule out any focus of infection to narrow the differentials but the likelihood of all the probabilities is less than viral gastroenteritis ( stomach flu).

Meanwhile following precautions will help.
Drink only well-sealed bottled or carbonated water.
Avoid ice cubes, because they may be made from contaminated water.
Use bottled water to brush your teeth.
Avoid raw food — including peeled fruits, raw vegetables and salads — that has been touched by human hands.
Avoid undercooked meat and fish.


I hope it helps. Take good care of yourself and dont forget to close the discussion please.

Regards
Khan

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