It’s fine to keep the music in, just remember that unless someone has explicitly given you permission you need to ask first.
There is plenty of Creative Commons music out there that you can use although if you do that you need to make sure to follow its license. I have an article about that at https://beesbuzz.biz/articles/6910-Creative-Commons-summarized - for what it’s worth, the music you used is now available as by-nc-sa (although it wasn’t yet at the time that you put it in your game), but since your game isn’t also by-nc-sa you still need to ask permission first.