Thanks a lot for trying out our game!
You actually do get points for hitting the boss, 5 with a melee and 2 if you shoot, but it's not necessarily that noticeable and should perhaps be more points (it made more sense when the score naturally went up much slower, but it should probably be double that now). I do plan on adding an effect on the score so that you see that more clearly.
Also, you can attack projectiles to destroy them. Not sure how to make that more clear though.