I have a congenital pectins excavatum. could it be the reason i find it hard to catch a deep breath sometimes and experience a lot of pain after high intensity workout (after getting hit there by forceful impact)? what could be done about it?

The limitation placed on the volume of the chest cavity does limit the potential for lung expansion to supplement air intake. Reversal of PE is has been accomplished for cosmetic reasons. In older kids/teens it involves cutting open the chest wall, elevating the sternum (breastbone) and stabilizing the new position with metal bars that will be removed later. It may/not be covered by insurance.