One year for a five year old is 1/5 of their life.
One year for a fifty year old is 1/50 of their life.
This is perspective perception at work. A year seems like a shorter amount of time, and seems more quick for a 50 year-old BECAUSE it's a much smaller percentage of their life than it is for someone younger. A fruit fly lives for about 40 to 50 days. A day for them is more SIGNIFICANT than it is for us, because they have less time.
No one is going nuts.
And even if time is ACTUALLY speeding up some, children would still perceive a year as a more significant amount of time than a grown up.
So let's break some things down.
The first question we have to ask is:
What is time?
You are definitely going to have to give us a definition of time. And you are definitely going to have consider PERSPECTIVE. If time was sped up for everyone everywhere in the universe, how could anyone in the universe actually measure that?
If you're just talking about the sun speeding up around the earth, as the measure, that's a different story.
If you're talking about everything on the planet aging faster than it should as a measure of time, that too is different. (Like people aging a year in a single day or somesuch).
But if the sun is going round faster, and the year is passing more quickly and people are talking faster, and aging faster, having babies faster, thinking faster, if it takes less time for the second hand on the clock to say a second has gone by, and everything else is in sync--you can understand how it would be difficult to perceive.
This is fiction, so you can reach beyond the realm of the likely. On a practical level we might not notice time speeding up if it was on a cosmic scale, but, if there is a localized effect, it could be. The solution is perhaps some kind of wave or uneven effect so it would be. So time could be passing more quickly on earth, while just a day passes in the rest of the universe--if THIS were true, if we were in a time bubble, we would be able to see that the stars aren't moving as they should be.
I think the trouble that people are running into is the universality of the question--you should make it so that earth is now running at a different time than it should IN COMPARISON to everything else--it's the sort of thing that needs a different perspective, and would not work on a universe-wide level.