Is 6 weeks to early to detect a heart beat? I am so scared

My last period was 23 June so it's says I'm about 7 weeks & I have tried to calculate from ovulation date I think I would be somewhere around 6 weeks, I really do not know how these things work because it would be my first time after a missed miscarriage the baby's heart had stopped..I am totally freaking out I'm paranoid about my symptoms disappearing,I google daily about miscarriages(not trying to be negative at all😞) I just want my lil one to be okay, iv tried to push my appointment to 9 weeks(husband does not want to) I want to know if my blueberry is okay,I just don't want to get my heart torn to pieces it will break me💔