I'm glad you liked it!
At first I was going to add some music but I didn't have much time so I tried random music but it was bad so in the end I just didn't add music. Same with a few sounds, I was going to add a sound for when you dodge a bullet that passed really close (like grazing in touhou games) but I still had to make the Title screen (I didn't use any game engine so that took a day or so) and fix some issues.
Also I probably spent too much time with the text to speech that tells you the score.