okay for a begginer
it was nice but there's alot to improve.
now the animation was poor, it looked like everything in the flash are locked in a grid, the enemies are unrealiscly dumb, and you made the black umm... ball invisible, what's up with the red shield?
make more situations rather that the black ball comes from one end of the screen, the enemies somehow miss him and then he somehow kills them. do like someone is coming from above, below, and stuff.
overall - not bad