Brief Answer:
several possibilities can be there..

Detailed Answer:
Hello XXXX, Welcome to HCM,

I've gone through your query and understand your concern for your wife,

As per your description, the first concern is Acute gastroenteritis (a stomach bug), a self limiting condition only needing supportive treatment (correction of dehydration, electrolyte supplementation, anti-emetics and pain killers etc.)

The Second possibility can be an acute infective diarrhoea (specially considering the smelly loose stools)..

There are certain other possibilities like gall stones(which you've rightly pointed out), even acute appendicitis(unlikely considering the symptoms started after eating outside sandwich, however not impossible) and also acute/sub acute intestinal obstructions (similar presentations but also presented with sudden onset abdominal distention), since you haven't mentioned any abdominal distention so i believe this is also unlikely..

Please let me know the color of the stool..

Is it completely watery/ mucus containing/ somewhat formed ?

Is the frequency of motion increasing ?

Is she able to eat/ drink ? Is the vomiting increasing ?

The most important thing right now is to compensate for the ongoing fluid/electrolyte loss..

So please let her have ORS solution immediately, 1 XXXXXXX of WHO-ORS in 2 ltr of Mineral water and let her drink gradually over the next 2 hours, repeat the same and let her drink it in next 4 hrs, repeat the same and for next 6-8 hrs gradually..

Hand hygiene and proper hand washing with anti-bacterial solution is extremely important every time before and after using wash room..

I'd not advice any pain killers/anti spasmodics, as they'll only mask the actual symptoms and can prolong the overall process..

Please keep her under strict observation, and if you notice that the symptoms are not improving within another 5-6 hours and if she's not able to tolerate any thing per orally, then I'd advice you not to delay any more and take her to your nearest Hospital/ ER for a immediate physical check-up, relevant investigations (CBC, LFT, KFT, Blood Gas analysis, Stool R.M and Culture sensitivity, USG whole abdomen and a few more depending on the clinical findings), and intravenous fluid and electrolyte replacement, antibiotics as well as other necessary measures as per the findings..

Let me know if there's any further queries, i'll be glad to clarify..

Also let me know how she stays in the due course..

Take Care
Kind Regards

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