I'd say around 13-15. One day I just became really self-conscious about sounding "stupid," even around friends I'd known for years. It all went down hill from there - to the classic symptoms like feeling like everyone was looking at me when I walked into a room, or whenever someone laughed it was because of me. Awful times!
I'm so glad that I've finally gotten past that. I credit age, experience and my job - it's very social, and has given me a lot of exposure.
I still have anxiety, but I've come a long way. I'm pretty functional.
I can recall being overwhelmed by anxiety in elementary school..even over little things. It did not become unmanageable until my early twenties. I missed out on my twenties and all the fun peers seem to have had/ are having.
As long as I can recall although it got noticeably bad during and after high school. I am better now than I was in my 20s but still have anxiety issues. And I believe I always will. It's learning how to deal with them, I do alright for the most part. But there is plenty of room for improvement.