Brief Answer:
INFECTIVE DIARRHEA

Detailed Answer:
Hi...
Welcome to Ask a doctor.
I am Dr Ajeet XXXXXXX
According to your symptoms,you are suffering from gastritis,abdominal infection and inflammation of stomach.This is cause of hyper acidity,bloating and flatulence.

Commonest causes of Acute Diarrheas after meals is an infection.This is called Colitis.
It can be bacterial infections such as Campylobacter, Salmonella,Shigella, Yersinia,E. coli,clostridium etc ,a viral infection (commonly referred to as the "stomach flu") or a parasite infection such as Giardia (Giardiasis) or amoeba(amoebiasis).
These bacteria often cause symptoms like diarrhea,cramping and nausea.I usually go for stool examination to demonstrate it.
This needs specific antibiotics or anti parasitic drugs(like anti amoebic drugs).
and I give a two week long course of antibiotics to such patient,specific for abdominal infection.

Take small frequent meals instead of large 3 meals.Avoid fatty and greasy meals.Have more of fiber.De stress yourself as overthinking and anxiety augments the symptoms.Do meditate and be physically active.
Please have bland meals which are easy to digest and take dinner,at least 2 hrs prior to sleeping.
Avoid junk and fatty meals,as they are hard to digest.Avoid gassy foods.Have plentiful water.
Go for a 20 minute walk after meals and be physically active.Avoid tea,coffee,spices and alcohol.
Abdominal infection and inflammation can lower down the absorption of nutrients,electrolytes,vitamins specially vitamin B12 and iron causing deficiencies and hence weakness,lethargy,easy fatigue,malaise and disorientation.
Replenish salts in your diet,which you lose in diarrhea and keep yourself well hydrated.
Take rich fiber diet.Have raw veggies and fruits.
Avoid milk and milk products if you are not able to digest them.
You can have PPI like Pantoprazole too.

Second possibility is microscopic colitis which is a distinctly different illness than ulcerative colitis.Inflammation of the cells lining the intestines can only be seen when tissue is looked at under a microscope and can not be seen by naked eye.The cause of microscopic colitis is not well known.Its symptoms include persistent or intermittent episodes of watery diarrhea after meals.But usually there is passage of large amount of mucus in stools in such patients.It is managed supportively and symptomatically.

Don't use strong anti diarrheal drugs like Imodium as they may cause gastroparesis and distention.
Hope that I have answered your query.If you have any doubts,please let me know.
Stay healthy and stay blessed.
Regards

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