Q: I changed my user name. Now on the same user I can't see any files

Hello

I am operating a MacBook Air OS X Yosemite 10.10.3. As it is a used device I changed the Username on "Systems preferences" I unlocked the padlock, and I continue until I changed the name.  After resetting the laptop, none of my files were there. My desk was empty, my apps weren't there, just the basics Safari, Iphoto, Itunes survived.

However, looking at the remaining storage, the numbers didn't change. Asides I wanted to access to some folders and I couldn't. A popup said, "That I didn't have permission." So the files, apps, are somewhere hidden. I just want to get back how the things were before. I want to have access to my files.

Please help to get back my laptop. It would mean the world to me.

Nicolás Vergara.

MacBook Air, OS X Yosemite (10.10.3)