The 25-year-old singer, Lady GaGa, was seen breaking down in tears in documentary footage recorded in her dressing room at Manhattan's famous Madison Square Garden venue.
She wept as she opened up about her insecurities, saying, "I still sometimes feel like a loser kid in high school."
"I gotta (sic) pick myself up and I have to tell myself that I'm a superstar every morning so that I can get through this day and be for my fans what they need for me to be."
GaGa was questioned about the incident during an appearance on "The Ellen DeGeneres Show", and she put her emotional outburst down to nerves, telling the host, "That was a huge benchmark moment in my life. I'm 25 years old. I was asked to play Madison Square Garden. Sold out five nights and quite frankly it's very overwhelming..."
"Well, in that moment I was very excited and nervous. Do I feel like a loser sometimes? Yes, of course I do. We all feel like losers sometimes."
The footage is part of a concert film called "Lady Gaga Presents The Monster Ball Tour at Madison Square Garden" which will air in the U.S. on 7 May.