tender breasts :(

never really had tender breasts before so idk if it's what i'm even feeling but it's on my actual chest. no where near the nipple. i  can feel the pain from inside and i'm just curious if that's what it's supposed to feel like? i also have pretty big breats ( i decided to throw that in there just in case women with bigger breasts normally feel the pain) don't really know too much about it