Gender utrasounds.. PLEASE READ

Desiree
I didn't really know what to title this, but a when I was 14 weeks pregnant I had an ultrasound done due to some bleeding I was having just to check on the baby, and the doctor said it LOOKS like I'm going to have a boy. We go August 6th for the actual ultrasound to find out the gender. But I've heard of the ultrasound that soon being not that reliable because even I couldn't exactly see what she was talking about and it didn't seem to look like anything but the bone in the leg to me. 
Anyways, I'm just wondering if this has happened to anyone (being told they think it's a boy and it ending up being a girl). Just out of curiosity. Because I also read that the male parts don't really start developing fully that soon. Maybe I'm just crazy, lol. I already have a son so I'm really hoping for a girl this time and even though old wives tales and stuff aren't accurate most of the time, along with the Chinese gender predictor, which I also used for my first, all of the signs are pointing to a girl. And with my son I didn't even want a girl because I had a feeling he was a boy and he was. This time I just have a gut feeling it's a girl. So again, just wondering if anyone's ever had the ultrasound thing happen to them?