Brief Answer:
Lump might be the xiphoid process; take medicine for indigestion

Detailed Answer:
Hi,
Thank you for posting your query in Healthcaremagic.com.
This is Dr. Swarnava Dattagupta answering your query.

I understand your concern.
First of all, you have given a short history of your problems. You have not mentioned facts like how big is the lump, since when it is present, the feel of it- soft or hard, is it painful or not etc.
At the bottom of sternum, there is xiphoid process, which can be felt when pressed or palpated in some people. In has a bony-hard or firm feeling, and might present as a lump.
Otherwise, in people suffering from bloating and gas, stomach might be distended and may present with a diffuse swelling over the upper abdomen.
There are other causes too, and an Ultrasound of abdomen would be required to tell further.

However, for bloating and gas, I generally suggest the following-
Diet modification- intake of dietary fibers and lots of fluid, avoiding rich fatty food, taking small frequent meals at regular intervals, avoiding alcohol and smoking if any.
Regular exercise in form of brisk walking, cycling, swimming etc. It enhances metabolism.
Pantoprazole-levosulpiride daily for 3-4 weeks will regularise bowel habits and take care of indigestion. Also, antacids after meals will be helpful.
Probiotics like lactobacillus for 2-3 weeks.

Get back to me with the answers so that I can help you further.

Hope I have answered your question.
If you have any further questions I will be happy to help.
Regards.

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