Miscarriage - HCG levels

I was hoping to be one of the lucky ones who didn’t have to experience miscarriage, but here we are.

Found out we were pregnant with second baby last month. My first appointment was scheduled for yesterday to have ultrasound and what not. Yesterday I should have been 7w2d. I woke up bleeding yesterday morning and when I went in for my appointment the gestational sac was only measuring 5w2d, and it was empty. My HCG levels were only at 761.

I was curious if anyone knows what their HCG levels were at the beginning of a miscarriage? And how fast it took to drop back to zero.

I’m so heartbroken. I feel like I’m always going to wonder the rest of my life who this baby would have become, boy or girl?, what would they have looked like, sounded like. Just sucks. 😞