help i don't know what's wrong

Ok. Well on August 10th I started cross country. We'd run 5-6 days a week depends. And my last period was August 24th. I'm 14 and I never did 'it' ever in my life. It's October 23 and I did not start yet. I have anxiety and always worry and I feel stressed mainly in school but I haven't started and I'm scared would I be pregnant!?!?!? I mean. I know how babies are made but.  I NEVER DID THAT EVER. And I'm still scared like I don't even know why. Because last year my period was normal during cross country