Inverted nipples, how ??

I have got inverted nipples for 2/3 years now (I'm 21) and I don't know why...I'm planning to see a doctor but what I saw online doesn't explain why I started to have them recently because in my teenage years my nipples were out 😅

Anyway, do you know if there is any way to make them out naturally (without surgery)?? I have to admit it's not really good looking and I am a bit ashamed of them ...😟