This is a pretty nice game. It is playable and once I figured out how to upgrade, it was pretty fun. Endless enemies is really nice and it gets quite challenging as time goes on. Nice work!
A few critiques:
* A start menu would be nice. Starting right in the thick of battle makes it really hard to get going.
* It was awkward initially was not knowing when I was taking damage. It could be nice to have a knockback / audio / flashing to indicate you were hit.
Very nit picky here but I had fun.
Really great work for 1 week :)