It is important here that you are using the King James Version of the bible. The NIV bible obscures this prophecy from Jesus, by replacing 'shortened' with 'cut short', which has different implications.

Jesus was speaking of today when He told us that the days shall be shortened. That is exactly the driving force behind the phenomenon that we interpret as "time is moving faster today". Jesus said it best when he said that days will be shortened. Days are actually shorter than they used to be. We interpret that as time moving more quickly, because we define 24 hours to be the time it takes for a day/night cycle to complete.

Since the early 2000's the day/night cycle has been gradually increasing in speed, to where we find ourselves today. Because many time keeping devices of today rely on vibrating crystals, it is possible that most time keeping devices have increased in speed to keep up with the faster day/night cycle.

We can feel that less time makes up an hour, or day, or year. It is not just because we are getting older! It is more than that! They used to teach us to count accurate seconds with 'one mississippi, two mississippi' but this method of counting is much too slow, today. Try it out yourself with a stop watch.