Is there any sign that I was hit by a crazy old man while crossing the street?

A madman is a person who suffers from serious mental illness, can't restrain his behavior, or behaves strangely.

The madman on the roadside is generally the former, which means that he has no ability to restrain his behavior. In this case, the madman has no judgment. He doesn't know that hitting people is wrong. So, you can only admit that you are unlucky and go away quickly.