Time flies like an arrow.

Everyone feels time passing. The perceived speed at which it does varies; we hear talk of “fast weeks” and “slow days” and “long hours”, mostly depending on how much you’re enjoying yourself and how much you have to do. This is normal. 

Most people have a reasonable sense of how long things take - they can usually tell, with reasonable accuracy, how long they spent on one activity or another without having to think too hard about it.

I lack this ability. 

For me, time is very fluid. Unless I’ve been able to look at a clock and measure how long something takes, I’ll have no idea. If I’m estimating how long something will take, I’ll need to compare it to things for which I’ve already done this and it isn’t always accurate.

If I’m estimating how long something has taken (without having looked at the clock), I have to think about all the things I did, how long I’ve measured them to take, and add it all up to give you a figure. Every. Single. Time. I can’t gauge it on feeling.

For instance, while I was in the emergency ward in August, I was in a bed and unable to see a clock. I also had very little to do. The only thing I had to measure time by was how frequently the machine measured my blood pressure (it was set for every half-hour). I was genuinely surprised when the first half-hour had passed because my best estimate was that 5-10mins had passed. I wasn’t waiting for anything specific and I had nothing to compare the passage of time to, as nothing was happening. The other interesting thing is that, for most people, this would have felt like an eternity.

I have a similar thing with driving - I have no idea how long a driving trip takes if I haven’t monitored it by clock or figured out how far it is, how fast I’d be driving and done the math.

Some pockets of time drag on, usually when I’m waiting at a traffic light, but not as frequently as the pockets that speed along past me, and a lot of people don’t realise just how abnormal it is until they’ve sat with me in the hospital and realised that a half-hour of doing nothing feels like 10mins, where an hour of working at a busy checkout feels like 8.

Yes, the feeling of how long things take varies for everyone, but for me it varies to extremes and is also erratic enough that it's a wonder I can tell the time at all.