Very impressive game considering it was made in a week! I love the theme going on here, where you're controlling different types of cells with their own abilities and win conditions. It keeps the game from being repetitive. I also like the different enemy shooting patterns, it really does make the game feel like a bullet hell. The white curvy bullets are especially fun to dodge.
I would increase the visual contrast between the walls and the background more. They're really similar in color, which makes it hard to tell when you're near a wall. It's especially a problem in the stage with the moving walls. Some levels are also considerably more difficult than the others (looking at you, platelets), so I'd considering some rebalancing in that aspect.
Overall, excellent game. I spent a while playing it and getting a high score.