Wednesday night may have been the “American Idol” debut for Rihanna. However, a fearless performance was delivered by the superstar of “Rockstar 101,” her new single.

In an “Entertainment Tonight” interview, Rihanna said, it’s the first time I have performed on “Idol.” It was kind of nerve racking. We are busy with tour rehearsals which has taken up a lot of time. We had to fit it in.

This week the singer announced the “Last Girl on Earth Tour” she will be undertaking with Ke$ha. She confessed the performance was completely spontaneous and revealed that she and the band made up what they were gong to do at the spur of the moment.

In addition, Rihanna explained what the meaning was behind the “Last Girl on Earth Tour” title. She said I think I am the Earth’s last girl because people sometimes make decisions based on other people’s outlooks. For me it’s my life. It’s my world. I will live it how I please. That’s the way I think about things. I am focused on myself and my work. The space is really narrow. I am focused.

“Rude Boy,” the third single from Rihanna’s album “Rated R,” is holding Billboard’s Hot 100 top position for the fourth week in a row. Rihanna said this is very exciting. I can’t believe of all the songs that “Rude Boy” is the album’s biggest song. That’s the one I wrote most on.