I called it spinny brain. Can I please just get through one thought before 20 more come crowding in?
It gets better. Your description is right-on though.
The best things I've found are limiting caffeine as much as is humanly possible, and exercise. I didn't add fully caffeinated coffee back until about six months. I didn't need any faster thinking, jumpiness etc. thank-you-very-much.
You've got this. Don't pick up a drink.