So worried about my 12 weeks appointment on Friday

I saw the baby at my last appointment at 8 weeks and everything was great with a heart rate of 171, the I went to a 4d clinic at 10 weeks 5 days to get blood drawn for the gender (it’s a girl!) and saw the baby moving around with a heart rate of 171. For some reason before my ultrasound at 10 weeks and before this one I’m so worried about the baby not having a heart beat anymore.. I’m a FTM and I worry to much I guess. Is this normal!