Started to get nerves over excitement for tomorrow's Anatomy scan. Any chances that they won't be…

Started to get nerves over excitement for tomorrow's Anatomy scan. Any chances that they won't be able to see gender or tell me much info? I'm going in 19 weeks Thursday, but kinda starting to think the what ifs... what if babies not active enough will they still be able to run all the tests / images they look for. will they get to see the genital area to tell boy or girl?¿? Prob should be getting some rest, But gotta love insomnia minds just racing away!¡!¡