Super nervous

I need some reassurance. I took a bfp test last week and set up an appointment through true care today, found out I was 3 weeks but it was too small to see anything. I had a miscarriage last year and pretty much the same thing happened, I wasnt very far so they scheduled me 2 weeks out and said there should be a heartbeat but there isnt. I guess I would like to know when you ladies heard a heartbeat and if any of you went in super early like I did but still had a success story.