Thank you for your reply.
This pain is likely due to costochondritis (inflammation of the cartilage that connects a rib to the breastbone) which can cause a sharp, aching or pressure-like pain and usually located on the front of the chest, but can radiate to the back, abdomen, arm or shoulder. This pain can worsen when taking a deep breath or cough. Please refer the below link to know more about this condition:
To relieve the pain you may take medications such as Ibuprofen and also do stretching exercises which can be taught to you by a physical therapist. However for any chest pain which is new it is advisable to consult your doctor who can do a physical examination to rule out any cardiac or lung condition causing the pain.
The breast swelling also needs an examination by your doctor. This may be due to fat necrosis in your case because of its sudden onset. However other conditions causing swelling in the breast need to be also considered by your doctor.
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