you made a mistake in the past and learn from it now, you are using clock time. On the other hand, if you dwell on it mentally, and self-criticism, remorse, or guilt come up, then you are making the mistake into "me" and "mine": You make it part of your sense of self, and it has become psychological time, which is always linked to a false sense of identity.

Eckhart Tolle

from The Power of Now: A Guide to Spiritual Enlightenment