Finally played your game, I was trying to play all games with low ratings amount first.
Sounds are good but as others said they are really loud even with my system volume set at 30%, and the wood does stop spawning fast for me too so I was unable to score more than 160.
On the other hand I also liked the sprite fliping direction and the wood mechanic, you could also make that when killing enemies there is a chance of them to drop more wood.
A tutorial for the keys would be nice, but you can also add it on description.
Very nice game and fun to play overall! :D