Ultrasound today.. please help a nervous mom out

So I had my first ultrasound done today to confirm pregnancy, and I would be 8 weeks 6 days and would leave me at a due date of 12/8/2020. After the ultrasound tech was done she told me the baby was measuring 6 weeks 4 days and she can see a heart beat of 118, and normal would be 120. They have me going back in two weeks to check development and everything, but when I saw my mid wove she said there is a 50% of me miscarrying this baby because it’s not at a heart beat of 118 and I know my period last month was 3/3/2020. My question if since I went in at 10am, had no breakfast yet, no vitamins since I can’t hold them down early so I take them in the evening and I haven’t had any water yet before my appointment for I didn’t wanna have to pee too bad, could that have effected the outcome of the ultrasound? I’ve had two previous pregnancies and they both were this way but never told I will probably miscarry... thank you if you read this I just need some peace of mind yeally to get me to 5/18 when we do another ultrasound. I haven’t had any bleeding or anything too which was weird for them to tell me I’ll probably .. I also wanted to add that I found out I was pregnant 4/18 and that means I would have only been 2 weeks and my test was dark when I took it which was weird to me to hear I’m 2 weeks behind