hello, I'm sorry about your trouble. You mention you are from India, but did not mention where you are now. If you are in the US, you may be reacting to the change in diet. Remember even the water is different in the US; most paces add fluoride to the water, and I think all add chlorine to the water. You might be sensitive to those.
Are you able to eat dairy products? Maybe your digestive issues are due to lack of the right "probiotics"; try eating yogurt (be sure it has only natural ingredients, NO aspartame).
Also: if you are in the US, be aware that most foods here are hybrid or GM (genetically modified). Those foods are banned in India. Many Americans have digestive troubles which build up gradually over many years, so it can take many years to realize there is any problem. You may need to avoid all wheat products and only eat a few grains such as millet, rice, teff and a little oats.
Perhaps a very bland diet will help for a while, until you can get to see a doctor.
Hey Nitin!
Well, without a clinical evaluation it would be difficult to determine the cause of your symptoms. Possibilities that may need to be considered include dietary causes, infections, inflammations, GI motility disorders, neuro-muscular causes, hormonal/ endocrine issues, medication side effect etc. I would suggest getting this evaluated by a primary care physician initially and depending on the cause diagnosed/ suspected, it can be managed accordingly or specialist care may be sought.
Hope this is helpful.
Take care!