Lorde, 17, worries people will stop liking her music when she is no longer a ''hyper-youthful being''.
Lorde worries she may not have a career by the time she reaches 25.
The 17-year-old singer has been praised for capturing the spirit of today's youth in her music, including hit song 'Royals', but she admits she isn't sure people will care about her music when she grows up.
She explained: ''Since I started making music, a lot was made of how old I was and it made me think about, what happens when I'm 25? Will people still like what I'm doing? Will it still be important if I'm not this hyper-youthful being?
''It's stupid, I know I'm being silly, but I can't help it. It's just one of those things. I'll get over it.''
The 'Team' hitmaker also reveals she is conscious of the pressures to look perfect in the music industry and how it might affect her fans.
Lorde said: ''I am a young person and I know how it feels to have those pressures of not looking a certain way. A lot of people have misconceptions about this industry and how you're supposed to look. I don't think I should have to look perfect all the time.
''I definitely think about the imprint I'm leaving on people my age - particularly girls. I'm sensitive to how women are portrayed because sometimes it kind of sucks.''
The New Zealander thinks she has ''thicker skin'' than most and isn't easily offended by detractors claiming she looks older than her years.
She added in an interview with Bliss magazine: ''I always get these weird people being like, 'Oh, she's growing up too fast, she looks 30.'
''I've grown a way thicker skin in terms of my own appearance. People don't hire me for how I look, but for what I do and the talents I have, which is cool.''
The BBC drama starring Aidan Turner returns to BBC One on September 4th.