Friends who never understand you

I have this friend and the other day we were talking about baby fever. (I'm 23 in college and living with my boyfriend. She's 21 working on a master's and still at her parents) I told her I honestly wouldn't be upset if it accidentally happened and my boyfriend wanted one regardless. And she gave me the most horrified look. I could tell she judged me. What I don't understand is why she would, I feel pretty happy where I am at in life and wouldn't care in a happy accident happened. I know that no matter how ready or old someone can be no one is actually prepared when the time happens. But I'm not going to just have a kid on purpose so I'm kind've upset she acted the way she did. Rant over