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1.The history and symptoms suggest that the lump what you are feeling could be the xiphisternum, which is normal anatomical condition - if there was a mass
ultrasound would have been picked.
2.The pain in that region most commonly are gastric causes / ulcers and inflammatory condition.
3.Treatment in this case includes having small portions of food in frequent in intravel of time regularly will help.
4.Avoid junk,spicy,fat containing food and take more of fruits and salads, fibrous diet for better bowel moment - that should help, you try at least couple of weeks.
5.If you have a suspicion and you want to clear once for all - then CT abdomen is right choice - that will clear all your suspicion and help to find any underlying pathology.
Good luck.
Hope i have answered your query,
any thing to ask ? do not hesitate to ask.
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