If you are so much unsure, you can go for a investigation called holter monitoring where your ecg is monitored over a day to look for any abnormalities. And also your lifestyle points that you could be a candidate for an increased risk of gastritis. The caffiene in the soft drinks also contributes to it. Gastritis can also at times can cause chest pains. If that is the case, I would have recommended my patients lifestyle modifications along with medications like pantoprazole to address the gastric symptoms. I would also advice regular physical activity and a well balanced diet to keep your cholesterol under check. Do discuss the above options with your care giver. Hope the above information helps you. Thanks.