Is it selfish not to have children?

I'm not old enough to be having kids just yet but I was having a conversation with my grandmother yesterday about how it was for her raising my father, we got onto talking about whether or not I wanted to have children and I said that I didn't think I would want to, as I think it takes away alot of your freedom and I'm the type of person to work long hours and move around alot and and I wouldn't want to subject a child to that, I then went on to say that if I was to consider having children I would much rather adopt as I think it's nice to give a child a home who has maybe lost their parents or been disowned. Then my grandmother started getting quite annoyed with me saying it's selfish not to settle down and have children when you're perfectly capable of doing so. What are your views on this?