when is your next ultrasound?

Wr
Just wondering when everyone's next ultrasound is? My first was at 8 weeks and all went well. My doctor said I won't have another one until 20 weeks!! That just feels SO far away! I am 12 weeks and not showing at all yet...which I know is normal but I just wish there was more evidence of the baby growing inside me! Sometimes I still feel like it isn't real. Anyone else feeling this way?