Umbilical cord was in the way and the doctor couldnt see the of my baby?

about a week ago when i was 15 weeks and 2 days preggo i had gone to the hospital because i was having bad pain in the abdomen area and they did an emergency ultrasound. the tech said she was 70% sure that i was having a girl. today i went to the doctors office for a regular check up and the nurse decided to do an ultrasound on me just to see the growth of the baby. when she called the tech she came in and i told her what the hospital tech had said about me having a baby girl. so she told me oh lets see if its true. she turned on the ultrasound machine and started to do the ultrasound. she told me oh nooo this baby is not cooperating at all. the baby had its legs crossed and she told me to walk around to see if it moved. when i came back she tried to do the ultrasound again to see if baby was cooperating. she tried for about 10 minutes, and still nothing. then 5 minutes later she told me the umblical cord was like on the way and she thought it was a boy but she couldnt tell if it was because of the umbilical cord being on the way and giving her a bad view or not. anyone ever had this happen to them and then it turned out to be a girl instead of a boy? im so anxious cause i had bought girl stuff already :(