I have always had very anxious tendencies, even when I was younger. I have learned how to manage it somewhat better for the sake of my sanity and comfort, but it still rears its ugly head in myriad ways. For example, sometimes I overthink things way too much and it makes simple tasks very difficult, like when I was first starting to build my PC. Or I ask questions of others that seem very abnormal and unusual, and they often laugh at me because they don't understand why I'd concern myself with a little, and sometimes irrelevant, detail. It sucks, and of course, as in your original post, I worry about the worrying which makes me worry more.
I have two main defenses against the cycle...I have one friend who is pretty much the opposite of me, she says nothing ever keeps her up at night and her life is very straightforward. And if she catches me being unnecessarily anxious she manages to help me figure out which worries are just silly, and which worries may have some validity. And the other thing I do is, go against my impulse. So say, sometimes I feel a lot of anxiety about my bedroom being messy or my bathroom, because I worry it's going to mold overnight, lol. So I consider cleaning it every day, or after every usage (which for my shower, is twice a day, and the sink, numerous times). I tell myself not to and force myself to stick to my one cleaning per week schedule, no matter how worried I am about mold spreading.
Or if I'm socially anxious, the more scared I am, the more important I know it is for me to go do that thing, see that person, or be in that place. My impulse tells me to hide, so I act against it. Between the things I do and the help of a very understanding friend, I manage to do not so bad anymore.
