Very complete game overall! Love the fact you can run out of ammo and you can change weapons and pick up powerups as well. The rolling mechanic was very cool too. Interesting art and I really liked the music.
It does have some things that can be improved tho - I got stuck in the wall a couple of times because of being shot by a lot of things. Also the walking is a bit too slow and takes a bit of time to start,if it is snappier I think it would be a big improvement. I managed to get to the last boss but I could not get past him because he just wouldn't die, I kept firing all kinds of weapons at him, even stood right in front and just spammed. He didn't seem to want to chase me either so I couldn't get him out of the way.
Great work, especially since the engine is yours!!