Hi... Welcome to healthcare magic. As per your complain you have problem of heartburn problem that may be because of gastritis or gastroesophageal reflux problem. Lack of water and less high fiber food may lead to loose stool problem. Avoid more fatty food and gaseous foods in diet. Drink more water per day.. Do some excercise at morning time. Avoid immeadiate lying down after meal. Elevate your head during sleeping time. Avoid citrus foods ,coffee, chocolates etc.. Avoid heavy meal and fatty foods at night time. Proton pump inhibitor drugs helpful in acidity problem.. Consult a gastroenterologist for further diagnosis. Endoscopy examination can done for further diagnosis. I hope my guidance helpful to you.. Take care. Thank you.