It would be a whole lot better if you could shoot more than one bullet at a time. I often found myself jumping to shoot the red skull that comes down, miss because my timing was off and I have to wait for the bullet to clear the screen before I can shoot again. But by then I keep getting hit by so many skeletons that I can't get a shot in and I end up dying

Other than that, cool game

I really hate how you have to start back all the way at the beginning every time. It's so frustrating to make it so far only to have all they way back at the very beginning

Perhaps you make some checkpoints? For example, you could make a checkpoint where the dotted line splits into two paths