reassurance

I am 13w and 1 day. I went to my monthly appointment today and she asked about my miscarriage in oct17 and then we listened to the heart beat and it took her almost 8 minutes to find it. every appointment I am absolutely terrified till I see or hear baby. so the heart rate was 110-116. She kept telling me it was normal at this time and it could be tricky to find. But at 8 weeks it's was 170. She stepped in the hallway to talk to the nurse and I heard her asking how far along I am and brought up my miscarriage. She came back in and I asked for a ultrasound and she said it is okay that I'll come back in 4 weeks and they will do my normal appointment. I'm still just worried. have any other mommas been through this and everything been okay?