first appt seen but could not hear heartbeat

Brittany
Went to my first appt today and baby measured 6 weeks and 3 days. The tech could not pick the heartbeat up but we could see it but it looked slow. Have follow up ultrasound on Tuesday to see if baby has grown and if we can  pick up heartbeat. Anyone else have this situation and good news? This is my fourth pregnancy all ended in miscarriage.