Am I infertile?

I’ve been sexually active since I was 16. Honestly I don’t like using condoms but I make sure me and my partner(s) are always tested. I’m 21 and I’m not trying to have a baby quite yet but I’ve also never been pregnant at first I thought I was just “lucky” but now my periods have been months apart and I’m afraid I’m infertile. Is there ways to see if I am besides going to the doctor?