NEW YORK -- Susan Boyle says sudden fame hit her like a "giant demolition ball."

The Scottish singing sensation tells NBC's "Today" show, in an interview to air today, that adjusting to her overnight celebrity has been difficult.

Her first appearance on "Britain's Got Talent" earlier this year had millions of YouTube hits. After placing second on the TV competition, the former church volunteer was hospitalized for exhaustion.

When asked if she felt overwhelmed by fame, Boyle says: "It's a lot like a giant demolition ball." Boyle says she had to wrap her head around the experience, but is glad for the opportunity to have a professional singing career.

Her interview on the NBC morning show was taped in London last week.