I have probably the weirdest question..so i wouldn’t call it an insecurity but mostly me being curious. why are my nipples so different than others?

i almost want to show a picture because i’ve searched up different types of nipples and haven’t come across one even a bit similar. my nipples aren’t small but aren’t CRAZY big, they’re kinda like pepperonis but at the very tip there are what look like tiny bubbles and a small opening in the middle. is this normal, i just have no idea .