I like the music and the art is pretty good and clear for a 3D game made in 48 hours! Great Job there! The font on the start screen is basically illegible, though, so maybe simplify it a bit
I was really confused about the goal at first. I tried going straight for the spider, thinking that it was the goal. Despite all the experience I have with flies and spiders, I didn't realize that I was in danger and trying to escape. Maybe a different feel for the music or some more visual focus/intimidating animation from the spider could help? (Or maybe a mechanic where it's trying to reel you in every so often?)
Some of the platforms were a little difficult to read where the platform started and ended. Since this is functionally a 2D game, it might've been clearer to use more of a rectangle-y shape for the leaves the player can jump on instead of what it appears to be now, which is a slope. Also, having some leaves be jump-able and others not was a bit jarring. And I thought for a while that the goal was to jump into the big plant in the middle because it was moving and making noises. I had no idea I was supposed to kill the spider until I read the game description online.
Lastly, rushing from one side of the screen to the other to lure the spider around means that the jumping controls have to be really good. There were times I pressed spacebar and no jump happened, and I missed my shot at luring the spider. Tightening up those controls (or maybe just making hitting the ground clearer? Maybe I'm hitting early because I think I've landed when I haven't?) could really help ease the frustration of that part of the game.
But overall, I can see this being extended into multiple levels and being a really sweet game!