Fait enough :)
For the music, i think its really cool to make them yourself, like the art.
But you should do that only if its something that you like doing.
If you hate doing music or art, there are tons of free open source asset you can use.
At least for prototypes, game jam, stuff where you need to build quickly.
But if making the music is a great moment for yoou, then of course yes do it :)