Lungs and Airway1 Comment
WHAT IS IT WHEN I COUGH, THERES A PAIN UNDER RIGHT BREAST FEELING LIKE A POCKET IS ABOUT TO POP. AND LYING ON THAT SIDE IS UNCOMFORTABLE
You should have a chest x-ray because it is difficult to isolate the exact cause on just these symptoms. If there is pain when applying pressure on the chest in that area, then it is likely that it related to the chest wall. Injury to a rib, or even a fractured, strained muscle and so on.
However it could also be related to internal structures, like the lung and the lining around it known as the pleura. Patients with pleuritis do tend to experience more pain when lying on the affected side. Cardiac conditions would be more central or towards the left but could also account for right sided chest pain.
What is also important to exclude here is the liver which sits just under the right breast. It could explain these symptoms that you are experiencing. There is no way of knowing for sure without further investigation by a doctor.
You can read this article on Right Sided Chest Pain for more information.