I think shes just worried about taking that extra step. She may love you as much as she claims but what you have to realize is women WORRY they worry and they worry even more when there's a child involved.
you have only being seing each other for a little more then 6 months. I think you should give her a bit more time, she didnt give you a flat out no she said shed have to think about it. In my opinion shes being cautious and you shouldnt take it to much to heart just let her have her time to feel comfortable with the idea of taking that next HUGE step.
Good Luck

Heidi