Headaches, Brain Fog, Dizziness after Rumination?

I get brain fog, dizziness and memory/concentration issues when I am struggling with rumination too. I get worried that I am damaging my brain too but it also makes sense that my brain gets tired after something like that. I have been trying to get a glass of water or make myself a healthy snack after catching myself ruminating cause sometimes I get so caught up in it I forget to eat/drink for a while, which makes me dizzy.

Obviously I'm not a doctor and I can only go off of what you wrote here, but everything you say sounds completely normal and expected to me. Excessive rumination indeed leads to headaches, brain fog, dizziness, and memory issues. That's just what happens when the brain is over-worked. The reason it feels like it's getting worse is likely because you're now worrying about these symptoms, which results in more anxiety, and then more symptoms. It's a snowball effect. Just think of the brain like a muscle. When a muscle becomes fatigued from overuse, it's going to feel crummy. Ruminating about your memory issues is like trying to do more bicep curls to check if your biceps still hurt. Focus on the root of these issues: stress and anxiety. As you take care of your mental health, these side effects will improve on their own.

Yup happens to me

Yeah a lot of my friends think I have ADHD too 🤷🏻‍♀️ it runs in my family but I was never diagnosed.