Gender speculation

I went to the doctor's office yesterday to have some blood drawn and for an ultrasound. After the ultrasound tech finished her examination I asked her if there was any way she could determine the sex of the baby since I am only 12 weeks (when I was pregnant with Cael we had an ultrasound tech tell us we were having a boy at 12 weeks). She said she would be more than happy to take a look, but made me promise I would not rush out any buy anything based on her prediction. I happily complied and waited with bated breath as she began moving the wand over my stomach. Within approximately 10 seconds she announced she was fairly certain it was a girl. It was interesting because she didn't appear to base her assumption solely on genitalia, but mentioned that there was a distinct difference (although minute) between boys and girls at 12 weeks gestation and based on her experience, our baby looked like a girl. I have been convinced we are having a boy for the last couple of weeks so having this information will make the 20 week ultrasound that much more interesting. I have another ultrasound on April 2nd so stay tuned!!