Carrie Underwood says even though she has "only-child syndrome going on" she's not a "sociopath".

Despite having two older sisters, the country songstress felt like an only child growing up as the age gap is quite significant between them.

Speaking in the June issue of Marie Claire US, Carrie says her upbringing has had a negative effect on her personality in some ways.

"I'm not a mushy person at all. We were never a huggy family. Or a 'let's talk it out' family. Technically I have siblings, but they are quite a bit older than me. I was the accident, so I have the only-child syndrome going on," she admits in the new issue.

"I'm a little more selfish, a little more independent, a little closed. I do wish I were softer. I wish I were able to form relationships better. But hey, I mean, I'm not a sociopath."

Carrie rose to fame after winning American Idol in 2005. The blonde beauty's world changed overnight, which was initially very overwhelming.

"At the beginning of my career, I used to have panic attacks. People were touching me, screaming, it made me really nervous. In public, I just get nervous. It's a physical reaction, feeling like the walls are closing in," she revealed.

"The fans are great. It's not their fault. I don't ever want to come across as ungrateful. But on my end, it is hard for me to process. Because I am still just me."

Carrie is happily married to hockey player Mike Fisher, after tying the knot in 2010. The 30-year-old star says her beau calls her "the queen of awkward moments".

"Anything that can be made awkward, I will make it awkward," she laughed.

Despite being in a stable marriage, Carrie added that she's not ready to start a family just yet.

"I don't feel old enough to have kids. I know I am mature. But being responsible for another human?" she mused.