I love the concept of a rhythm game occurring whilst also performing a task in the background! For me it gets a little out of sync with the music over time. I also cannot see how to move the spike ball!
My suggestion would be to make the lines that tell you when you need to hit shorter because the window to press them is actually quite small or it sounds out of sync, but the line implies you can click at any point during that 0.5 second window!