Help me out please!!!

Had a great appointment this morning at 11 weeks and 2 days pregnant until I went in for my ultrasound. Baby’s heartbeat was 188 bpm and heart tones sounded great. The dr came in afterwards and said that there is fluid around the babies belly and behind the neck can anyone ease my mind and explain what’s possibly going on? They are sending me to a high risk dr and I have now having to get the genetic testing done.