Yo Tycho!
Welcome to Pixelation! 
Dope stuff, good feeling. 

Some of the shapes could be cleaner, like the left side of the stool and other places.
Sounds like you were on a time budget tho.
Good on you for focusing on completion rather than perfection.

I question the placement of the ash tray and tea cup.
It adds a nice messy, too busy to think straight, risk and charm to the piece.
Tells a story and draws interest, so the fact that I question it is good.
Maybe add more wrongly placed items?
Or maybe just a couple is good enough?
Dunno.

As for using lines or solids, there's pros and cons to both.
So use whatever is going to flesh out the current step and and help you move to the next.
A nice combination is to draw solids and then cut into them with erased lines.
Experiment to find what feels good for you and always modify your process to fit what you're working on rather than a standard.

Redoing parts isn't a realistic concern.
Editing, improving, fixing, refining, etc, is just the nature of art.

Personally I prefer a bit of warping and wrong perspective.
But that's just my taste.
Of course it's better if that's intentional.
So if you want it more regular, def fix it up

For embedding youtube videos use the yt tag and the video id found at the end of the link.
Like this:
[yt]iOKECERd6KE[/yt]Changed it for you.

Welcome aboard and happy pixeling!