Brief Answer:
suspected food poisoning,follow the advice...observe how you stay afterward

Detailed Answer:
Hello and Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concern...

Well, from your description, this seems like a case of acute gastroenteritis (stomach bug) which you probably contracted from the Chinese buffet...

First and foremost, drink plenty of water, electrolyte-rich drink (coconut water, Gatorade etc.) throughout the day to avoid dehydration during this phase. You can buy WHO-ORS XXXXXXX (Oral Rehydration solution sachet), it's available globally.

Empty a pack in One litre of Mineral water, drink it in an hour or two...Repeat the same thereafter, continue it till the feverish feeling goes down, urine output normalizes, the frequency of stool decreases...

For tenderness around the stomach area, you may take a mild analgesic like ACETAMINOPHEN (eg. Tylenol) 650mg up to thrice daily.

Ensure to wash the hands thoroughly with antibacterial hand-wash before and after using the wash-room...

Have only and only Mineral Water...

Eat in small portions but at regular intervals (have 4-5 small meals a day rather than having 2-3 large meals)...Have some simple and bland foods (as in the toast, rice, mash, crackers, yoghurt), salads, curd based diet, avoid any form of spicy food...

It'll be better to get the motion analyzed (Stool routine analysis and culture sensitivity assay). Based on the results, you'll most probably need to have antibiotic therapy for a few days as well...Please discuss this with your doctor and proceed further...

Let me know if I can assist you further.

Take Care
Kind Regards

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