15 week elective ultrasound... Gender?

So I had an elective ultrasound done at 15 weeks. I couldn't wait any longer to find out. Right after the tech started the ultrasound she called it a he. My mom was like oh you already know it's a boy? The tech said no that she calls all babies he's until she knows. We let it go and continued with the ultrasound. Baby was very wiggly, it took her a while to even get the heartbeat because baby was moving so much. Then towards the end she said okay well I have seen stuff go by a few times... It's a boy!  We were excited and went out shopping. A few days later I couldn't sleep, something was bothering me about the ultrasound, funny thing is my mom couldn't sleep the same night because she was thinking about the ultrasound. We didn't find that out til the next day (pretty weird!) anyway the next am I for up and went through all the pictures and the 20 minute dvd. There are two spots where it looks like she is pointing to gender, they are both completely different. Plus I have found one or two pictures online at the same gestational age that look identical to this picture... 
 I'm so confused? When I first got pregnant I swore up and down it was a boy. Then slowly I began to think no I think it's a girl. Then she told me boy and I was like should have never doubted but I am doubting big time. My "boy" shot does not look anything like any boy ultrasounds I have seen. And like I said I have found girls that look the same as the first picture. Any one have any thoughts? The place I went to offers free rechecks to confirm and I go back Thursday. But it's driving me nuts!! I won't have my anatomy scan until the end of February or beginning of March with my OB.