I have reread Peter Hoegs' excellent book 'The Borderliners' where he examines in depth the concept of time. I'm fascinated that it is a constant but goes faster and slower depending on what you are doing. If you have your hand in the fire it goes very slow but if you are making passionate love it goes very fast and is it constant when scientists can't invent a clock that stays accurate!
We think of time as linear, that is going in a straight line, with events happening that haven't happened before but we need to measure the passage of time against something as we do when we judge the speed of a car coming towards us against the constant background or the hands of a clock against it's face. But sometimes events do repeat themselves so maybe there are two times, one linear, and one cyclic which stays the same or repeats itself. Imagine if linear time is moving constantly right (why does it seem natural to me to be heading right?) and we are measuring against cyclic time which is on the bottom half of a circle moving left so it appears that linear time is moving faster and conversely when it is on the top half of the circle it would appear to move slower.
OK now all we have to do is control it consciously. When we are enjoying ourselves we make time move slow and when life's a bitch it's a rollercoaster!