I often times draw circles in my head. When my brain is thinking, it's like there's wheel that is spinning and churning. It doesn't bother me, as I'm used to it, and doesn't cause any problems. I think also a lot of it is perception, you noticed that you're not the same person as you were in high school. Maybe you just grew out of that phase, and is onto another phase of life. I also had a bad OCD issue back when I wasn't on my meds(not intended to treat OCD). So I know that certain medications can help, even if your issue is not OCD, it is worth bringing up to a doctor.

Best Regards,