Really good job. Did you watch “The Last Beer”? Recent animation also with sliding beer.
You had the most important thing first: a good idea. You had good characters too. And music. And sound.
You suggested about the shading/lighting. I think the characters could be lighter and the background darker to help them stand out. I think the bottle should fall right after the guy falls, but then take a little bit to roll away. And I was surprised the bottle rolled off the back; I thought the wood board was flush against the wall and it makes more sense for me if it rolls off the front.