Notes app notes are GONE

so I have a mac that is linked to my iPhone 5s. notes I have written in the past on either device would automatically show up on the other device. I was playing around with the Notes app today and I discovered I could move individual notes into folders. I moved one note and it brought me to the page where I had four lists ICloud, My phone, Notes, Gmail. But now I can't get back to the "main page" and like a good twenty of my notes are gone or lost or not accessible. How can I get back to the "main page"?? I don't understand why this happened I sure I didn't delete anything.