I have a peculiar problem on some days my stomach is fine and on some days I feel little uneasy, sometimes their is a feeling of incomplete evacuation. I burp even after 4 to 5 hours of taking lunch if I walk some distance, and also In the morning when I practice yoga and breathing exercises. I am unable to understand what the problem is with me. I do not have constipation and my diet is healthy. I also practice yoga on empty stomach in the morning.