I like the hand-drawn background. It adds a lot of charm and reinforces the dream setting.
The character's movement speed made running around collecting coins a little tedious. The fact that you have to run around the same area several times didn't help.
After a while, the framerate started to get worse and worse. I think this is because the cannonballs weren't despawning.
After getting both sets of special coins, I fell in the hole in the bottom and the screen went black. It didn't seem like I could do anything else, so I closed the game. I assume this was a bug, because your screenshots show more of the game that I wasn't able to see.
Congrats on your first game jam!