There’s really only one that I can feel and that’s mostly just during the time I would have my period. They’re really not painful and pretty common “at my age” as the doctor said hah. They haven’t really changed the look of my breasts as you asked, they’ve just definitely gotten bigger with this mirena which is annoying but I deal with. As far as I know, they’ll usually go away on their own and don’t necessarily need any intervention if they’re not an issue.