What Causes Discomfort In The Lower Abdomen Upon Eating?

How does a patient know if he/she is having gall bladder issues. After I eat I get the feeling of indigestion/heartburn like , especially in my lower abdominal area and under my rib cage; and feel better if I pass gas. This started 24 hours ago. The only thing I have eaten that is common is a bagel thin (wheat/multi-grain).