It's nice, I like the style and the story sequences in between the levels.
The platforming experience is all right, but mainly it felt quite unresponsive. I can't count how many times I missed a jump because double jump didn't work, and the wall jump was troublesome as well. And fluent movement and good controls mean everything in a platformer game.

But the rest of it was fine. A couple more details:
– It was unclear which key affects which door. I collected a key and pointlessly kept jumping into a door, but it wouldn't open because it needed a different key (and keys unlock doors instantly instead of requiring you to go to the door, so there's probably no need to display the key onscreen).
I'd use a matching colour for the padlock, so that you don't need a lemon-coloured key to unlock a pink lock.
– The pumpkin has an exclamation point next to him. At first, I thought it's a "NPC" and you're supposed to talk to it… well, you're not.
– The number of jams you have can go below zero when you die (and probably shouldn't).
– The arrow keys move the entire page. See here for the fix:
https://www.newgrounds.com/wiki/developer-resources/unity3d-webgl-support#wiki_toc_3

I think fixing the double jump's responsivity is the most important change to make, the rest of the game is quite good.

I can't really seem to get past level 2, I think I'm supposed to take the key to the ice cream sandwich, but it's not really opening up? A pumpkin enemy seems to be perpetually blocking it too. Since I can't get past this I can't really judge the game much, but I can give you feedback on what little I played.

It's overall not bad. I like the crispy clean artwork of it and some of the designs are nice! Though some are kind of confusing. I also like that you implemented a story with comic cutscenes which is always an appreciated detail, but in general I have trouble grasping what the tone of the setting is supposed to be. The themes of candy and simplistic, cartoony visuals make it seem like a cute, funny setting, but some other things that are jarring (pardon the pun) such as the backgrounds and the overall story make it seem like it's supposed to have maybe some surrealism to it? It just makes me feel confused though rather than any solid feeling.

I would touch up on the world and the story a bit. I would go for more simplistic backgrounds too but if the backgrounds are supposed to be distracting, that's fine, it's just hard to get past them. (maybe they could use a little more contrast since the character and enemies kind of blends into them)

Finally I would polish the game a bit. I got stuck several times on objects (maybe input a damage recoil) and my little jam dude sometimes would just not jump for some reason. The game feels kind of sluggish at times, personally I would make a platformer a little quicker.

Again, sorry if I did something wrong so I couldn't progress! But I hope my feedback will be helpful. You have a lot of talent, so I hope to try a game from you again!

EDIT: Okay, I managed to finish it now! I think you have a real knack for platformers, and a great sense of design. I realize now the world you've built is probably meant to be more alien-ish? That's a pretty original concept, I'll make sure to keep following the series so I can get a good sense of it. Just keep going for that polish and I think you can make a really popular game! :)

Awesome! This game however could use full screen mode, because on smaller screens the game doesn't fit in and when pressing arrow keys the screen keeps scrolling. However - Good audio, great animation, unique character with an awesome story, Good job!