Good for a quickly-made game, however there are two main negatives.
The first is the awkward boomerang. Mostly you will be spamming little short goes nowhere throws. Why? Because somehow the length of throw corresponds with the length of mouse button press. I guess it makes sense from a how boomerangs actually work perspective but it's completely counter to intuitive game design, which would suggest the boomerang should always go a medium distance (not long and not short) every time you click, and ignore length of clicks. This also would go a long way towards feeling right for the player.
The second negative is the follow-the-player "AI". Most enemies are of this type, and it's one of the most annoying possible kinds of enemy (aside from enemies that spawn directly on the player -- not a problem this game has but is the other primary annoying type). It's annoying to play, but worst is it takes almost no effort to program when all you do is set enemy destination x and y to player x and y. A single enemy or two of this type might be acceptable, but they shouldn't constitute the bulk of the enemies. I realize it's a quick and dirty technique, and when you're under a time constraint maybe you do that, but it's bad design.