How do i know if i am having a pigeon chest (pectus carinatum) or man boobs (gynecosmatia)?

Bone vs soft tissue: Pigeon chest is a chest wall deformity. Gynecomasty is enlargement of the breast tissue in males. Pigeon chest does not jiggle and does not cause breast tenderness.

Pigeon vs Man Boobs?: These are two completely different diagnoses and present differently. The pigeon chest implies a congenital deformity of the middle portion of your bony chest bulging out whereas gynecomastia is a condition affecting the front &lateral or sides of the fleshy part of the chest i.e. Breasts and occurs during puberty or later. See your pcp and s/he will be able to guide you better.