[Much like the wind that swirled around with a few fallen leaves, his mind whirled and buzzed with thoughts that would continue to move around, but never leave.] I can't think of a good way to describe thoughts like the 'wind.' Can anyone help, or does this already sound good enough?
Sounds good to me.
If you want more detail, add "autumn" before "wind" and it'll be more obvious what you mean.