gender help!

i had an elective ultrasound yesterday at exactly 16 weeks and the baby wouldn't cooperate. legs crossed at ankles, hand down on parts, and cord between legs. this is the only image after 30 minutes of trying of what she said is his potty parts and she's positive it's a boy. I'm just not sure? could it be the cord? I already have 2 boys and honestly with them it was clear as day penis and scrotum.

help? opinions?