fetal doppler - 9 weeks 6 days

So I have my fetal doppler from my last pregnancy and since yesterday I've tried atleast 4 times to try to hear the heatbeat and I CAN NOT find it for the life of me ! it's so frustrating ! I didn't get my doppler with my first pregnancy till 13 weeks and even though it took quite a while the first time I used it , I found the heatbeat .. I just had an US Tuesday so I know baby is growing right on track and perfectly healthy but I just can't find it on my doppler ! 😭😭😭😭