If you want to put a stop to the thoughts you need to do something that requires you to think about something else. Like exercise, playing a game, watching television, those are things that help me. But…
It’s not a long term solution it’s just a quick patch me up.
If you want to fix it long term, you’ll have to teach yourself to trust yourself. The reason you’re doing those things is because you don’t trust you will do the right thing, or what is needed in specific situations. Or that you’re worth little to nothing.
What works for me is actively noticing when I do things good in situations where you haven’t prepared. Also try to note and remember how ok it was when you weren’t prepared. Compliment yourself. I.e. my password for my phone is “I love you man” so I’m saying this to myself a bunch of time throughout the day.
I now got in the habit to say yes to things before the doubt and analysing can start. To, in certain situations, start doing the thing without thinking.
I used to do it with tiny things like, popping in at a friends house, then say yes to going out for a drink without knowing where, who’s going to be there etc.
Then bigger things like not looking up where a place is I have to be and never been before, so I can prove to myself I can figure it out without the hours of analysing and stressing.
And last of all, I recently started asking myself where would I be if all the worst case scenarios come true? What would be the worst implication? And the thing I realised is that the fear in itself is the worst. If what you fear for happens it’s most of the time not really bad. Sometimes the worst thing happens without you having had the chance to analyse it in advance and I didn’t even realise it was that bad, cause you just fix it at the time.
tldr; short term: distract yourself
long term: learn to trust yourself, consciously complement yourself on good things, try to expose yourself to anxiety inducing situation a bit at the time and consciously understand and remember how good you did and as a last, most of the time you fear fear itself.
Hope it helps, cheers bud
Much like you, I’m an overthinker and suffer from mild-moderate anxiety on a daily basis. I don’t go to therapy, did some sessions when I was a lot younger and dealing with severe depression. It’s useful I think if you’re not quite aware of your problem and that it’s irrational, however once you are, it’s just a lot of encouraging you to do what you know you should be doing.
What I recommend is depending on its severity, ride the small ones out, and in a safe and quiet place if need be. Sometimes the best thing you can do is to accept that it’s coming and allow yourself to go through the motions and be done with it.
However if it’s something which keeps niggling at your brain all day, do something easy and repetitive. I play video games or watch Netflix, sometimes accepting I’ll probably waste a whole day doing just that if need be. Chores really helps too- mundane, but while I’m moving, I’m too preoccupied to think about it.
Thirdly, I also exercise to tire myself out so that I don’t think about it.
You need to make peace with it, and remind yourself the problem itself is either temporary or will pass, or even though it’s a pain now, you won’t even remember it this time next year.
Good luck OP.