THAT WAS AWESOME for your first game, congratulations!! I’m sure it was a great experience. It’s so inspiring to see people learning and participating in jams for the first time. What you put together is a great tech demo, you proved to yourself that you can make any platformer.
My advice:
The camera is too close to the player, increase the field of view (watch other game's screenshot and try to count how many tiles high are in the camera view, in general it's around 12-14 tiles high), it’s hard to see what’s above or below. I couldn’t tell if I was jumping onto a solid platform or into a pit. Also, the mask counter always said “You collected 1 mask” even after I had collected all four.
But again, it’s fantastic that you made something that works! In fact, you’d be surprised, it works way better than some games I’ve seen in game jams, even if it’s just one level. Congratulations! Keep it up!!