Congrats on finishing the jam! This game reminds me of the old iphone game doodle jump in a way, but with traditional platforming instead of bouncing.
A couple pieces of feedback:
You don't need a timer. Just make survival the goal. The absolute maximum score I was able to get before the timer ran out was 11 (unless there's a way to add more time that I didn't find). Either way, the timer isn't a necessary addition. The fun of games like this is survival, not clock chasing.
When you randomly spawn platforms, you need to do some work to ensure impossible challenges aren't given to the player. I hit a case where the platforms spawned on the farthest left point and the farthest right, meaning the double jump wasn't enough to bridge the gap (or if it was, it would have been absolutely just barely, which is another game design faux pas. Make it clear what jumps are possible and which ones aren't by making the doable ones easily reachable, and the ones that are impossible not even close). As a part of this, I would also consider making the platformers smaller because the not impossible cases are a bit too easy at this point.
In a game like this, the platforms need to be jump throughable from the bottom. One way platforms were probably not a technical possibility due to time constraints, but if you were to keep improving this game i would recommend adding them. When 2 platforms are stacked on top of each other, not all players will realize strafe jumping is an option. (I found this out the hard way when I made a puzzle platformer that required strafe jumping for a jam once and the volunteer I had demo it couldn't solve the puzzle cuz it didn't cross their mind it was an option). "Janky" options like strafe jumps should be for finding hidden bonuses only, not a mandatory part of the platformer's design.
Congratulations once again on finishing this jam! I hope this is the start to a long and storied career