This is awesome! Great work for your first jam. You kept things simple and ended up with something quite complete. :D
The character movement felt very "slidey" and some of the jumps were quite difficult to just because of the visually rounded corners combined with a square hit box. a bit of "coyote time" and a bit less sliding would have helped the feel a lot.
There's also a small bug where the ending screen background doesn't scale with the viewport size even though the win text stays centered so probably just some forgotten anchor points. Not a big deal at all.
After a few tries I managed to get to the end with 29 seconds to spare!