Thanks for writing youur query.
After reading your post, it seems that you are having abdominal discomfort due to increased acidity and gas production in addition to the side effects of antibiotics. Some antibiotics disturb the normal flora of useful bacteria present in our intestines. These bacteria help in the process of digestion and absorbtion.
You should take antacid
20 mg to get relief from acidity.
Also take a probiotic
preparation, which restores the damaged flora of useful bacteria in the intestine.
Yoghurt or curd will be beneficial to you.
I hope this is helpful to you.