Yeah, whenever your in a directory and you need to cd into a sub directory, there is no need for the / in front of it. When you do that, it is trying to look for the directory on your / partition or tree.
Like this:
$ pwd
/home/drew/media
$ ls
mp3
$ cd /mp3
no such file or directory
$ cd mp3
$ pwd
/home/drew/media/mp3
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