I unfortunately wasn't able to "finish" the game (if there is even an ending) because the game became far too laggy by the time I reached the depth of the first long looking fish (it sort of bends when I bubble it, not sure how else to describe it)

This is an excellent concept! I really enjoyed going down, bubbling enemies, bringing them up, upgrading, and doing it again. 

I found it incredibly confusing when I first bumped into a wall and my character stopped moving. I'm not sure if my game was bugged, but I was stopped for very long. This is definitely a cool punishment mechanic for bumping into walls, but I feel it could benefit from being tweaked a bit. If my game wasn't bugged, I would definitely suggest making the "stopped" time shorter. If not shorter, instead of the player getting frozen, you can make them get slowed so they still have a chance of recovering from the wall bump. It would also be nice to have a visual indicator that I am stunned. Maybe some stars spinning around the head.

I found the gun/light aim got real janky when I tried to aim above me. 

This is a small nitpick, but I had no idea I could press E to pick stuff up at first. I thought I was supposed to avoid the fish and eventually stumble upon gems as I went deeper. A quick peak at the game description quickly cleared that up for me!

Like I said, this is a wonderful concept, but there are aspects that can be expanded on. I also super love the visuals. I did not play with sound on, so I cannot give feedback on that aspect of the game.