early ultrasound?

Elle
I'm wondering if I should get an early ultrasound or just wait. I had a miscarriage with my first pregnancy and I asked to come in at 6weeks because of that. Theyscheduled  me at 6 weeks 2 days. They did warn me we might not hear the heartbeat then. Is it better to try to go early to hear it or just wait? How many ladies heard heartbeats at 6 weeks?
Thanks!