Ok. Lots of things I'd like to say about this.
First some positive comments.
I think the premise (if I understand it correctly) is a good one. It's a very workable idea. It's probably been done a lot before, but I like it here.
The shot design is also really good. The placement of the camera is chosen rather well. What shows up in the camera isn't always great, as I feel we ought to be seeing more of this guy's face rather than his backside or his body and hands. But the placement and the use of shallow focus is visually interesting.
One particular shot I thought was the most surprising was when we first see the guy's reflection in the mirror, and water is either running down it, or splashing up at it. I don't know if this was a natural phenomenon of the shallow focus and the water warping the reflection, or if you did something in post-production. But the way the guy's face is twisted and smudged to where it looks like an oil-painting caricature was really shocking and bizarre. I loved that. If that was unintentional, awesome. If that was completely planned, wicked awesome!
I can also say that the color grade is on the right track. But the colors between different shots in the same location seem mismatched. You're also clearly going for a bleak and grungy atmosphere here, but there's a missed opportunity with respect to post-effect film grain, other bits of dust, hairs and artifacts you might find on 8mm stock or something like that. (please don't use digital noise if you decide to do that sort of thing. Film dirt would be better) And I feel like a lot of your shots could do with a dirty vignette around them. Something to bring in the sides, make them bleed over a bit. It would help make the film feel claustrophobic, which I think is the point of a lot of it.
But now for the hard critique.
The pacing is extremely slow. The content that you have, the ideas that you bring up, the use of sound effects over his actions and other elements are great. But they ought to be happening a lot quicker in order to bring us in. And like I said before, I think seeing more of his facial reactions would immediately make it feel faster without even changing the videos speed or the placement of edits.
The short is too damn long. My current short started out at the same length: 18 minutes. But it went by so much faster than your film does both because it had dialogue during its first half, and because there was always something going on rather than a bunch of slow long takes of stilted and stalled movement. I eventually managed to cut it down to 10 minutes, which is about as perfect of a length as we could have hoped for for what my story and content consists of. But your film "frequent frequencies," basically overstays its welcome by the 5 minute mark, if that, because we already get it. And it desperately needs some sort of resolution or at least some form of an ending right then and there, because the way you try to drag the point out further for another 13 minutes is just plain overkill.
And by the way, I don't miss the 8 minutes I ended up cutting out of my film, because the story didn't need them. I don't even know what those 8 minutes amounted to, because they were often halves of shots, a few seconds or a few frames here and there, slowly whittled down to 8 minutes. So because a lot of it wasn't even whole scenes missing, I personally miss it far less than I might have.
"Brevity is the soul of wit." Live by it.
While watching the first five minutes, I was the most confused by two things. A. the shots and moments involving whales and whale footage. And B. the sound effects of people, cars, and elephants.
What do these sounds have to do with the day to day barrage of stuff this guy must have to deal with at work? The sound of elephants may have seemed like a meaningful sound to you when you put it in the film. But to me, and I'm sure to many other people, it doesn't relate to anything. It doesn't represent anything to me that is obvious. Maybe if I worked in an office I could make the connection. But I've never heard of white collar people ever being referred to as noisy elephants, so the use of the sound seems misplaced.
Beyond that, everything that you have here is more than enough to make a killer short. You shouldn't need to re-shoot anything more, you shouldn't need to shoot anything extra, just work what what's there. Cut it down to 5 minutes tops. Shorten shots so that you can squeeze more in. Pick the best bits of his movements, preparations and reactions. Maybe use some footage from much later in the piece rather than working with the first half only. And like I said earlier, maybe give the color grade a little twist, in case it might change the effect of the piece at all. Definitely consider fake film grain and dust, a broad vignette in places, and maybe a more Matrix-like green hue to everything, or perhaps something yellowish, like a David Fincher film.
Best of luck to you.
EDIT: Kinda stupid to post a video on a forum like this and then not even come back to look at the replies. Often things like this don't get replies, as was mentioned above. But I mean, put a memo down for yourself--at least--as a reminder to go back and see if it got any comments. They can't always be bad, right?
Maybe I just spent a half hour writing this all for no-one. Lol (Silly me) But, this kind of stuff is always good practice for thinking critically about the pros and cons. And I do honestly think he has something here that can be reworked into a much better short.