How soon can you have an ultrasound done

Nybol • Tue, Mar 11 2014 • I`m 21,married been trying for baby #2 for 8 faithful months with glow. First BFP March 9 then MC On March 18.

Just fount out I was pregnant I'm now 3week and 6 days. I schedule withy doctor and she wants to see me on march 20 and do a ultrasounds.

How soon can you a ultrasound?