I struggled with this at first - it doesn't look like the camera was following the player so I couldn't see the hearts! After figuring that out I was able to exit out of full screen and scroll around to see the full level. I'd suggest looking at fixing the camera when you can. You can install a package like cinemachine to unity that makes it super easy to make it follow a player.
The jumping mechanics need some work too, playing around with the gravity and jump height to make something that feel more satisfying, it's very difficult at the moment because the jump is so tough! It's best to remember that on a Game Jam, make your game easy! It's better leaving people wanting more and harder than barely playing because it's too difficult. In 2d you can also apply a slippy material to platforms so that you don't stick to the side of them, it feel pretty clunky as is.
The art and levels are cool though, I think with some tweaks you can make this into a full platformer that feels fun. Good job and well done for submitting in 48 hours!