Lots of fun!
The gameplay's a nice twist on the classic agar.io/katamari damacy gameplay, and I like that there's more layers to it with the different colours and the different levels, increasing with size. It keeps it fun and interesting.
The music and the art was really good considering you only had a week!
For improvements, I'd just say growing bigger quicker, and maybe not going soooo fast, it kind of makes it even harder. It does fit the theme to some extent, but I feel like it's a bit more selfish than stronger together implies... I think maybe it would've worked a bit better if you stuck together with the other germs/blobs instead of eating them?
But otherwise, great job!