Infertility fears

I haven’t been to the OB/GYN in years. But of all doctors it is my least favorite. All my life there is nothing more that I have wanted than being a mother. I turned 25 this year and I know I really need to be in my best health. I have been noticing somethings that have really concerned me like excessive hair loss, irregular periods, and weight gain. I have also been having unprotected sex with my fiancé for 4 years now and no pregnancy. I am so scared that I am going to the doctor and will be told I can’t get pregnant and it will absolutely break my heart. The thought of going brings severe anxiety and actual tears. I am so conflicted. Sorry for the rant. I just needed to tell someone who might understand.