It's a metaphor where the world simply means lots of people. A variation of the above phrase is to have the world fall at your feet. Think of adoring people, prostrated in front of you:
I've never translated that phrase before. I usually took it figuratively, like the tearing-down of buildings.
When the phrase is used with people, I understand the phrase as the tearing-down of someone's feeling. I believe that a definition in The Free Dictionary: to damage or reduce the importance of someone or something, could apply to someone's feeling rather well.
Best Answer
Adele is talking about a time before she became successful and admired.
http://dictionary.cambridge.org/dictionary/english/have-the-world-at-your-feet
It's a metaphor where the world simply means lots of people. A variation of the above phrase is to have the world fall at your feet. Think of adoring people, prostrated in front of you: