I can't remember when it first started. I do remember when it started to interfere with daily life, about 22 years ago. The advice given to me by an MD at the time was "go find a shrink". I didn't know this had a name, and at the time I don't think I could even describe what was happening to me. Each passing year, I withdrew further from the real world and into the incessant machinations of my unfounded fears. I thought this was who I am.
Reading the GAD posts here, was the first time it even occurred to me that this was the problem, and not anything else I could conjure up in my head.
I have not been diagnosed or treated, I am working through turning off the anxiety stream myself.
I don't know how successful I will be, I'll have to get back to you on that. :)
Any improvement is a godsend.