I did quite enjoy playing but mostly I succeeded by being quite random with my key presses. It was quite possible to glitch around a lot which made some of the jumps too easy, but some were too hard! When I collected all the coins and then lost them all instantly it was too frustrating.

But it did look quite nice, I liked the subtle background and simple but bold graphics.

I like the game and how you need to explore to get further, but it is unnecessary frustrating. Some collisions on top are glitchy and also sometimes the game makes you double jump and sometimes not, also I can get the player stuck on some places thanks to the wall jumping. You should polish the game more and explain better how the wall jumping works and what B does since I managed to get all the 10 coins without it. For a first entry is impressive and I know you can only progress from here and now if you are interested on making games.

Fast and fun! And I came to say the same thing Warxwell has said :)

Cute first game! As Ellie said sfx would improve the feel a lot more.

Also, I felt some of the jumps (where the "floor" is near the top, like the image below) were kinda tricky to do since you have to walljump from an exact spot or otherwise the top will block he player's jump, after a few tries I found this to be kind of frustating. Still, walljumping is a pretty good and fun idea.

Pretty good game, congrats!