8 months, and nothing

We’ve been trying for 8 months, and nothing, I’m 20 years old, young and healthy, so why is it not happening? I just don’t understand. All my friends are getting pregnant without even trying and then there’s me and my SO. I got a text from my cousin today saying she’s pregnant and said “be careful our family must be super fertile it happened the first try.’’ Like of course I’m happy for her but when will it be my turn... what is wrong with me? Why can’t my body do what it was made to do?