Theories of time

Time moves quickly. I've finished my first term as an RA, made it through my first year of college, managed to achieve junior status after four terms.

Time moves slowly. My knee isn't really getting better, I feel this need in my gut to run, or at least achieve a level of workout, but I can't do anything. It hurts so bad to walk and use the stairs, so of course the elevator had to break, right?

Sometimes I wonder that our perception of time's speed isn't based on how 'In the moment' we are. I mean, when you are focused and using your brain's power to absorb all the details of the thing you're interested in, the time around you passes seemingly faster because you spend less time checking up on the boring sensory info, or the timestamps. So if you want to feel like you live longer, I guess do nothing.
That's so depressing, isn't it?
I miss those most exciting moments, you know? All the time, we strive for those moments and feeling that just make us feel so alive. That first kiss, the time you spent with someone who makes your day. The time you laughed so hard you fell out of your chair. The time you fell out of your chair and everyone laughed so hard.. haha.

And I'm sitting here now, ready for an experience, that I know will blink me to the next reference point and it will have become a memory instead.
Where am I? Is it like a solid state video, that I'm merely perusing from the future?
I wonder... and then I live instead.