Cycle day 60... 24 days late

I’m going out of my mind insane... I can’t take this anymore. TTC is the absolute hardest and most frustrating thing I’ve ever experienced in my life. 😞

I’ve made an appointment with my doctor, she can’t see me until August 20th but has me on a cancellation list. I just want answers... I need clarity. Why would I miss a period for so long? If I’m not pregnant, I’m getting concerned. I’m only 21.... I’ve NEVER missed a cycle. Maybe by a week or two but never this long. And this keeps being my answer test after test... countless brands too to double check. It’s always a BFN.