Los Angeles, Dec 22 : Rapper Nicki Minaj claims she was self-centered before she became a mother. The 41-year-old rap star shares a three-year-old son, who is known to the public only by his nickname of Papa Bear, with husband Kenneth Petty but said when asked what she had "learned" since becoming a mother that in the years before the little one came along, there were so many things she could do without thinking about anyone else. "Just seeing how much more you could love. Because my life was so selfish before he came here. I could do anything I wanted when I wanted. I could take my phone out for days, I could sleep for days, I could travel whenever I wanted to.' 'And since this little human came onto planet Earth, I can't do anything without thinking about him first," she said on "The Late Show with Stephen Colbert", reports aceshowbiz.com. However, Minaj went on to add that motherhood has been worth the sacrifice because her son's face is "worth more" than anything she could possibly buy as she joked she is thrilled to have "pushed him out" into the world. She said: "There's this thing that happens everyday when I see his face, which is more than anything money could buy in the world. And so, I'm really happy I pushed him out." The singer recently said that she has no idea why she chose Papa Bear as a nickname in particular for her son because she had initially planned to nickname him Bubba when she was pregnant. /IANS