Great work! I love the choice in music!
I do agree that the double spikes are a bit too difficult, but other than that the gameplay feels pretty great.
My one suggestion is more on the visual side and that's that the two windows (I think?) on the background are a very similar colour to the platforms and spikes, so initially on loading the game and a couple of times when I lose focus I'll read them as obstacles and try to avoid them. I've found a good rule of thumb is that if your foreground is dark keep the background light or vice versa.