For myself I have three main ones. All that occurred before the age of 10.

1. When I was young and I would be in the car, with obviously someone else driving, my brain made this rationalization: if there were more vehicles coming from the opposite direction than us, we were driving towards doom while everyone else was driving away from it.
2. If there was a thunderstorm I shut every curtain in the house to keep us “safe.”
3. After my Great-Grandmother died, I was 6, and I realized what death actually was, for the next few years I would have panic attacks that involved me screaming/sobbing for my mother. (To this day if I deeply consider life, especially the enormity of the universe, it will cause me to have a panic attack, but now I call for my husband instead of my mother.)

I wasn’t diagnosed with anxiety until I was about 14, when I had another series of panic attacks after someone my age from school died in a car crash.

However, I had a bad reaction to the medicine they put me on and spent the next years struggling to cope with my anxiety on my own. It was two years ago (I was 26 at the time) that I went to the doctors due to panic attacks, derealization, and suicidal ideation that I was diagnosed (again) with GAD and prescribed an SSRI. Thankfully, I was able to stay on the medicine long enough for it to start working this time. I’m doing much better now-a-days. :)

It was recently, within the past year, that I realized that those events and ways of thinking from my childhood were caused by anxiety and should have been red flags to my family (and me) that I needed some kind of help, i.e therapy.

TLDR: Did you have any childhood experiences that with hindsight you realized happened because of anxiety? I had (at least) three, took awhile to get help, but am doing better now.