Overthinking - how can I stop?

[Ohio8]

I often find myself overthinking after a situation, making up the worst case scenario in my head and wasting the day (sometimes weeks) worried about it. I still go about my day and do what I need to but it's on my mind 24/7 depending on what it is that's happened

How can I be more carefree? I've tried to remind myself "we'll cross that bridge when/if we get to it" but still my mind is racing and I need to think of plan B, plan C and plan D incase that scenario comes true - usually nothing of that sort even happens and it turns out ok

Any advice? How do you cope with uncertain times/situations without overloading yourself with the stress of "what if this happens, then what?"

Some of these things are so minor and when I talk to someone in RL, they laugh and say "why are you even thinking that? That's not going to happen" - so I realise i've got an issue and it's not normal to be this way

I spent the day yesterday reading a book, how to stop over thinking. It was quite good, and is all about grounding techniques at bringing you back to the present day. I am suffering with horrendous anxiety at the moment, so another thing I am doing is meditation on spotify. If you type in what you're looking for you'll find loads. I have always been skeptical about this, but I wish I'd done it sooner.

Also may be worth speaking to you or GP.

Some individuals are very very good at planning ahead, which always includes a plan a plan b even a plan c.
You sound like you are that type of person but, sometimes it becomes a habit to take every situation even small ones and overthink and plan for the worst case scenario even if it's very unlikely that there would be one in a minor situation.
Then it becomes hard to switch off in your head so I think as was suggested by a PP, meditation, the learned disciplined calming of the mind might help reset the tendency you have of overthinking everything that comes your way.
People can, and do, meditate when they're walking, when they're sitting on a bus, when they're taking a rest, you can do it anywhere and it does clear and calm the mind ,but you have to stick with it.

Thank you both for taking the time to reply. I do like the idea of meditating while doing everyday things like walking or washing dishes etc. I will probably start with guided meditation on youtube and take it from there. I appreciate your advice, thank you