What is a word or expression to describe anxiety about the passing of time?

What is a word or expression to describe a feeling of anxiety about the passing of time?

I am not referring to boredom which refers to not having anything to do or being dissatisfied with what I'm doing and wanting to do something else.

I am referring to the feeling I get when I contemplate that time has passed by, or that time is passing by.

This sounds like an existential crisis, with particular reference to

a new-found grasp or appreciation of one's mortality;

However, you shouldn't really be able to experience something so traumatic on a daily basis, while still being able to function normally.

Perhaps you are experiencing a mild form of chronophobia.