Spotify adding the music I listen to to the playlist I don't want it to.

[Synthz0rz]

Alright so, on the Windows desktop app, I created a playlist entitled "Stream" and it's made for, you guessed it, being a background music when I'm streaming games. However, I made another playlist entitled "Stream metal" that's made for, you guessed it, same thing just with metal music. 

But Spotify decided to scramble both of those playlists and now one playlist is added to another. Also, I made a playlist containing only carefully picked songs from a specific artist (in this case, The Cranberries) and Spotify decided to scramble that one into the past 2 so no matter if I select "Stream", "Stream metal" or "The Cranberries", every playlist contains all of the songs from each and every one of those playlists rendering the PLAYLIST in itself, useless.

Yesterday I noticed it just began adding everything I listen to to the playlist regardless if I added that music to any playlist or not. 

Please don't tell me it's intended behavior and tell me it was me who did something wrong so I can properly redo the playlists, otherwise I'll just have to go back to downloading MP3 files and making my own Winamp playlists like it's 2005 again.

Thanks!