Woah! That was awesome, haha. Can't believe you coded that all by yourself. Just needs a jump, or I thought maybe your boomerang could hit your forward if you don't mouse click again to catch it! (like your arm pops out ready to catch it, and if you don't you get a nudge that makes your jump or boost! The slide mechanic is really well done, I like that its slow when starting, and slide when walking.
Great ideas, and I love the colour pallet. Congrats on the first itch release, Stoked for the full game and levels!