Time flies like an arrow, fruit flies like a banana.
As most people would sort of know, time flies when you're having fun, and slows down when you have got a long wait ahead of you. I guess that it is partly in the mind. We may have internal clocks, just that some people are better at reading them than others. When the mind is occupied, then it is easy to lose track of time, especially instances when you are running late and things seem to conspire to make you more rushed.
There is a saying that 'a watched pot never boils' which I assume to mean that if you focus on one thing, then time can seem to slow. Also, when watching the second hand of a clock or watch, you may find that the second can seem longer, that some lag may appear somehow to slow it a little. Perhaps something like adrenaline can affect our perception of time, when athletes have to perform, or others who have to have quick reactions, like racing car drivers, fencers or martial artists perhaps.
Anyhow, I guess that is all I have for now, I could always return and add more if I have anything else [trying to think fourth dimensionally]. You will see an ETA if I do. (What does ETA stand for? Extra or Edited Text Added / Amended? There are some other acronyms and terms that I haven't figured out or learned yet.)
Would like to stay and chat, but it's now time for bedtime, goodnight :)