Sure, just tried it. First, I really love the tutorial song - haven't experienced that before being guided by hard rock music. Both fun and useful.
I like the general gameplay. It's satisfying to shoot things and get more weapons etc. which is the most important and fundamental thing here.
It does say 'click and hold down to move and fire', though it fires automatically.
Now, this is just my taste, but for a game like this I just want to get going without too many barriers. You've made a quite comprehensive system and the guide is a bit overwhelming - at least before you've played the game a couple of times. Instead you might consider (like another comment told me with my game) to make a playable tutorial that pauses and explain when the player encounters new stuff and mechanics - like you did with the song, but more gradual and with small text boxes popping up, for example when you encounter a new enemy or get a new weapon or shield.
It's nice that you can get different ships and upgrades, but again it gets quite complex for a game like this. I'd start with just one type available so you need to achieve to upgrade. The weapons options also add complexity, maybe unnecessarily?
As I said, I really like the feel of the game which is the most important thing. I would ease the player into it to not scare off more casual players :-)