Hi

Chest pain can be caused by problems in any of the structures in the chest, starting from the skin (some persons have painful skin rashes such as herpes zoster) to the fat and muscle under it ( it is possible to have inflammation of the muscles within the chest cavity).
Under the muscles the bones such as the sternum which is the bone to the front to the chest and the ribcage. The area around sternum can sometimes become inflammed in a condition called costochondritis (inflammation where the ribs join to the stenum). This is usually a sharp pain , to the front of the chest which can be made worse by movement of your body and taking a XXXXXXX breath,as you described, and in this way affect your breathing. If the pain due to costochondritis is severe and you are anxious as a result then in that way palpitations can occur.
If your press the rib joints (where they XXXXXXX the sternum at the center) and you feel pain then it is possible that it is costochondritis.
It is treated by NSAIDS such as aspirin , ibuprofen or cataflam taken on a full stomach and also by heat or ice application.

Further in from the bones would be the esophagus : this can cause pain in conditions such as gastrointestinal reflux disease and in esophageal spasm.
Esophageal spasm would cause the following symptoms such as chest pain, feeling as though something stuck in throat, difficulty swallowing, reflux and heartburn.
If this is suspected by you or your doctor , you may have to do imaging studies to look at the esophagus and it is treated by medication.

Pain in the chest can also occur is the lining that covers the lungs (the pleura) becomes inflammed. Pleuritic chest pain tends to be felt when you take a XXXXXXX breath or cough. It may be associated with shortness of breath.
It may occur with viral or bacterial infections of the lungs, as a result of trauma and in association with more serious conditions such as liver,kidney or heart failure, cancers or autoimmune conditions. It is diagnosed by a doctor based on description of the pain and also by examination of the chest with a stethoscope. (When you press the chest wall there is usually no pain like in costochondritis)
If pleuritic chest pain occurs as a result of infection, you may have a fever.

Other causes chest pain and shortness of breath related to the lungs would be pneumonia ( would usually have a fever and cough with this) , asthma or in some rare cases a pneumothorax.
A pneumothorax is a collection of air between the lining of the lungs and the chest wall, it can occur spontaneously in persons with no lung problems. It causes chest pain and shortness of breath.
It is diagnosed by a doctor based on history and examination ( decreased sounds on one side when listening) and Xray. In alot of cases they resolve without treatment.

Chest pain can also be related to the heart- inflammation of the lining of the heart can cause pain and shortness of breath , infections of the heart itself or if the blood supply the heart is reduced , chest pain can also occur ( angina). This pain tends to start out on activity and is associated with shortness of breath and palpitations. It is not usually associated with pain on breathing.

If the thyroid is hyperactive or you are anemic (low red cell mass where the red cells are responsible for carrying oxygen) then palpitations can occur.Anemia can also cause shortness breath, in very severe cases where the blood count is very low chest pain can occurr but again it is not usually worse on XXXXXXX breathing.

Although the pain may simply be due to costochondritis and may resolve with NSAIDS, it is usually best that all cases of chest pain be assessed by a doctor to rule out more serious conditions.He or she will take a full history, examine you and advise appropiated investigations based on the examination.

I hope this information is helpful to you and I hope that you feel better soon.Feel free to ask any other questions.

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