Hi Meredith,
Nice work overall, especially given the absence of direction. Unlike a lot of beginning composers, you have MATERIAL!! So many beginners just play a drone and "cool sounds," and you have real music here. You should be very proud of your work and definitely I encourage you to keep at it.
I particularly liked the (unfortunately short) material when the main character is drawing the circle. You have a solo trumpet, which the audience could associate maybe with that character (as he's solitary).
In line with other comments, for a short film (or even a long one), it's good to come up with a compelling piece of material like that and then work it in gradually. Sometimes there are cues that hardly do anything -- the visuals are telling the story at first, so the music could be just a few chords and a single chord on the piano, or even just a single note -- leave space.
Moreover, for a short movie, you just want maybe two main ideas. The jazzy thing for the would-be car thieves is funny, so I am not saying (and nobody is saying) you should confine yourself to just one idea.
The composer Carter Burwell is particularly adept at the slow burn stuff. If you have Spotify or Amazon Music, or something else, you could listen to his score for "The Good Liar." Tracks like The River Styx take a while to get going but then take off when the ground is prepared (so to speak). The first track on "Goodbye Christopher Robin" called "Tree of Memory" also starts minimally but then gradually goes somewhere, building up for nearly three minutes before making an emphatic musical statement. And then it returns to simplicity -- musically asking questions, not reaching conclusions (if you follow me).
Another way to think about it is "accompaniment without melody." Maybe there's a voice-over, maybe there's dialogue being whispered, maybe it's just visual. But, as
@José Herring wrote, "sparse in the beginning then more and more could have developed as the the story unfolded...."