The Idea behind the game was interesting, but it seemed to be a bit on the rushed side of things.
I also didn't really see the limitation of "Blood is Lethal" since there was no real blood.
If you were going for Flappy bird I would have examined how that game handled gravity and inputs. As you kind of go from 1 speed to -1 speed very instantly, while in flappy bird you usually do a quick jump up, then you gently sink back down until your speed increases so much you drop immediately to the floor.
If you need Software to develop art, I would reccomend GIMP2 to work on Pixel art, might be a fun project to refine this game a bit.