So, I think that there is a solid idea here with a few notes:
First, I'm not sure if there is a win state. I lost the first time I tried, but I'm not quite sure how, I assume I was shot too many times or something.
I thought that the direction I ran into blocks would affect the placement, but that wasn't always the case.
The cube and fire pixel art are really well done! I like the colors and would have loved to understand more about what each one does (maybe allowing some customization or something would help or something, but it almost reminds me of the gummi ship editor from Kingdom Hearts, if you know what I'm talking about).
I feel like the background didn't quite fit the style, but that was probably more of a time constraint, so no worries there.
Like I said, this is a fairly fun game with a lot of potential. Nice work. :)
I also feel like I should share my masterpiece of a ship:
