I am feeling pain in ribs. some times i fell pain in upper chest. i do yoga. it pains a lot when i do abs. why?

Costochondriti: I commend you for your desire for Good Health. “Feeling pain in the ribs and sometimes in the upper chest” is likely due to inflammation of the junctions where the upper ribs join with the cartilage that holds them to the sternum, called Costochondritis. Pain may radiate to abdomen which can be worse while doing abs. Focus on Meditation, stop postures which increase pain. See Orthopedic Physician