I really liked the idea! Honestly with just a very tiny bit of extra work (a little bit of polish, and maybe a score system based on how long you survived as well as the already existing system) I can imagine this being a really, really addicting game. Good job!
However I can't help but notice the game's called "one bullet v2" but I can't find v1 in your profile... Honestly just a minor nitpick tho :)