hi Lauren there could be 2 possible reasons for your pain and both are manageable in medicine we evaluate pain by 3 components focal ( site of pain ) local ( around the site of pain ) global ( remote location other than the site of pain leading to pain ) so the focal cause could be your bra cup edge may be pressing on the site and that is causing the pain solution - try using a larger size or apply some petroleum get before putting on your bra where the edges touch the body if your pain subsides with this than it’s the reason for pain local cause could be swelling in your breast as compared to the other side solution - try examining it by standing in front of the mirror and if you feel that the size is bigger than the other you should be referred to a breast specialist global cause - since you mentioned that the pain aggravates after eating it could be peptic ulcer disease ( in lay terms acidity ) as pain from acidity sometimes is referred to the chest region ( referred pain ) solution - start tap pantoprazole 40 mg once in the morning 15 mins before breakfast and if the pain subsides than we know it’s acidity take meds for 15 days and avoid spicy food drink 2 glasses of warm water before sleeping and after waking up conclusion- it doesn’t look to be a cause of major concern and can be managed with the above mentioned treatment if you have any queries regarding it or any other issues please feel free to write and I shall help you in the best way I can best regards Dr Raza Ali