You did a great job making a solid little game that works well in the time limit for the game jam. I fail to see how this game fits the theme of the jam.

I'm not a fan of games made for multiple game jams, it just screams that you aren't taking the trijam seriously and just want to get your own game to be popular by showing it to more people.

However you're a bit lucky, you're not the only zombie game in this trijam and I think the game is actually better than the other one. For instance, you actually had sound in your game and I couldn't just stand in a circle forever alive because the zombies AI were too dumb to get caught on architecture. (That's mainly because there's no background, but hey sometimes less is more). 

I think you could have let the zombies get closer before death. Some munching sound on death could have been nice. The player's off centre turning was distracting.