7 weeks 3 days am i going mad?!?

so for the past 4 weeks or so since I found out I'm pregnant I've noticed my heart rate has been elevated. (noticed this in my last pregnancy )(I've had 2 MC and a chemical) well now this morning I've woken up and notice my resting heart rate is lower than normal. usually 85-95 resting. This morning it was 69. the last time this happened in my last pregnancy I had a miscarriage. I'm not holding out too much hope for this pregnancy as the last 3 have been unsuccessful but I hate the fact I have to wait til Saturday to find out 😫 ultrasound is Saturday and I couldn't be more nervous. Ive never expected good new at any ultrasound I've been to. I was hoping this time I'd be lucky. I feel awful because I don't want to create a bond and get excited over this pregnancy if it's not to be. I'm in a real state atm. I just want my baby here with me 😓