Ahhhh so nervous

I'm so nervous that the dr got the sex of my baby wrong. After seeing a few different people saying this has happened to me it's making me nervous. From the moment I found out I was pregnant I imagined and felt like I was having a boy. (I am happy either way) but then at our ultrasound at 13 weeks they said girl!! I was shocked since for 10 weeks I felt like I was having a boy. Shocked but still so thrilled. Friends who knew were so schocked as well and to this day still think that the doctor is wrong. I've had 3 different friend tells me it's a boy not a girl. I'm 18 weeks 5 days. So now I'm doubting the doctor.  We've been imagining a girl for the past 5 weeks and are very excited. Even picked a name. I had had a vaginal and stomach ultrasound the day I found out it was a girl. I don't have my next ultrasound for 2 weeks. Please what are the chances they could be wrong since I had both those ultrasounds?? Has this happened to you?? Share your story!! Please.