U can hear it at 14 wks. I have the sane Doppler and u just have to have it sit low and apply more pressure. If ur not applying enough pressure than it will b hard to hear. I'm not saying hurt itself or anything but u do need to apply some pressure. at my drs office they always have med students come in with the Dr and every time anyone of them has tried to hear the heartbeat they never can just cuz they r being to gentle. My Dr and I have to tell them that they need to press a little deeper. Hope this helps and good luck :)
I have the sonob and found our baby's heartbeat at 6 weeks, now 17 weeks. Baby will be right below your belt line. Baby's heartbeat will be fast, don't mistake it for yours. Watching YouTube videos help too
At 14 weeks it is going to be low. Probably right above your pubic bone.