Anatomy scan concern

Michelle Marie 👗💖❤️‍🩹 • "...I will trust and not be afraid; For God is our refuge and strength...” - Psa 46:1

Just had anatomy scan (part 2) at 20 weeks for our second baby and was told I have to go get an echo done because they couldn’t confirm heart details due to maybe position etc.

His heartbeat is 128 and moving a lot.

Any one had experience with this??? Feeling a little nervous.