It is likely that you have gastritis. I would advise you to have antacids and a multivitamin. As per your BMI you are underweight. These following lifestyle changes may help: - Don't skip meals, you may not feel like eating but in such conditions you should have the reduced amount in frequent intervals(i.e. 3 square meals broken down to 5 or 6 as you can tolerate) and slowly increase as you get better. - Reduce/ Avoid spicy,fried, fatty, junk and oily food - Avoid/ Limit drinking coffee, tea and carbonated drinks to once a day - Exercise regularly (minimum 30 mins) - Increase daily intake of water to 3 liters - Avoid/Stop smoking and drinking if you have the habit - Reduce stress through methods such as yoga/meditation.