Decent take on an old concept, but...
The hit detection is a little off, and some of the blobs spawn outside of the spawn box. For this type of game, a health bar isn't needed, as it's an eat or be eaten situation. However, a couple of extra lives could be beneficial. At any rate, improve on the graphics, and maybe add a background. Obstacles would be nice, as it'd be something different, but you'd need to make sure the enemies couldn't pass through them as well.