No fetal heartbeat found on the first intravaginal ultrasound at 6 weeks and 1day. Should I be concerned? I have another appt scheduled in 10 days.

Clarification. I would clarify with your doctor what was seen. In some cases it is just too early to see a clear fetal pole to be able verify a live baby or not. At 6 weeks if there were clearly able to see a fetal pole then a heart beat can usually be seen. When I am faced with these scenarios I usually repeat the scan in 1 week.