Nice work, especially for a first game! Excited to see the updated version :D
I liked the subtle way you slow down while shooting and the movement itself felt great for dodging enemy bullets.
Ran into a situation where whenever I continued the game, it picked up right where I previously Game Over'd so when there were already bullets on screen the session would last only a few seconds.
The idea of collecting the oil is interesting and I'm curious what the reasoning was behind including that theme!