The phrase "head spin" means feeling very overwhelmed or confused, similar to when your head feels like it's spinning around because there is too much information or a situation is difficult to understand. Full definition
The prospect of a major change in lifestyle, relationships, and finances can make a person's head spin with uncertainty even if fixing the marriage seems impossible. (divorcesource.com)
But still, wearing the platform is a statement so be prepared to have heads spinning in the streets! (lebazhaar.com)
It can make a viewer's head spin trying to ask questions about how and why anything works. (combustiblecelluloid.com)