Owing to your age, I would advise you to go to the nearby ER and get a physical check up done since it’s been going on for some days.
It will help in removing other causes by doing further investigations such as:
Pancreatic issues
Gastric ulcers
Cancerous growth
Next Steps
Meanwhile you can take esmoprazole 40mg in the morning, empty stomach
Health Tips
Avoid foods that cause acidity such as milk tea/coffee/alcohol/raw tomatoes/
kidney beans/meat etc