Slightly inverted nipple?

Is this a cause for concern?... one of my nipples slightly invests. Not my entire nipple but just a small tip of it does. It doesn’t hurt or anything and it’s usually a little bit inverted. I read that it could be normal but I also read it could be a bad sign. It’s been like that for some time and I’m 20 btw. Sometimes it does come out and isn’t inverted