Acidity pain after eating outside foods.

I am at my relatives house one month ago , there i eat only paranthas not chapati and my schedule of eating is not good there was no time of eating food. sometimes we eat junk foods some time paranthas and no sleeping time will be there. After i came home i have some pain issue in stomach like gas pain , i go to medical store and say my problem and they gave me some medicines but after taking medicines it was relief , but some days after i thinking my stomach is paining after that my stomach was aching again and again whenever i think , and now the situation is like this whenever i eat outside food my stomach is like full of gas and my stomach is aching . It feels like someone is putting air in my stomach . i am 23 years old , can i never eat outside foods ? this problem will be permanent ? What to do pls help ?