I really liked the game! Killing "Nazi" vampires with garlic is such a creative and fun idea. The grandpa and the kid add a lot of charm and give the game real heart.
For the gameplay, I'd love to see a bit more variety in the vampires—maybe different enemy types or wave-based progression - and just a few more things to do as the game goes on. But for a game jam, this is really well done.
Great work, and good luck!