Brief Answer:
you need to Visit your nearest ER/Urgent Care at the earliest....

Detailed Answer:
Hello XXXX, Welcome to HCM,

I've gone through your query and understand your concern..

Now from your description it can be an acute bout of Gastroenteritis, but the swelling over abdomen and inability to pass gas must be checked out immediately..

It can be due to an acute/sub-acute intestinal obstruction which is an surgical emergency and can be life threatening if not diagnosed and managed immediately..

So please don't delay any more and call for help or call 911 or urgent care for ambulance, please don't try to drive on your own..

There are several other possibilities too, but we have to rule out the most severe one first..

I hope you've understood the severity of the condition, so please check in to your your nearest ER where they'll examine you thoroughly and run a battery of investigations(i.e.Chest X-ray, X-ray abdomen, CBC,Electrolytes, LFT, KFT and/ Cat-scan of abdomen etc.)..

Let me know how you stay in the due course..

Wish you a faster recovery and great health ahead..

Take Care
Kind Regards

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