I am 14 weeks. Had an ultrasound at 8 weeks. Only saw one baby and heart rate of 168. I used my Doppler for the first time and the heartbeat kept changing drastically. One second it’d be 135 then the next it’d be 165. Last week at my appt the doctor listened for a min and it was 145. Am I hearing 2 heartbeats or do they fluctuate that much? I could hear Another heartbeat of 120 but that sounded different and then mine was 80.