Early miscarriage

Brittanny
I need some thoughts. I am one of those people who test early. I found out at 3 weeks and 5 days that I was pregnant. However at 4 weeks 2 days I got my period. Now here I am one day post period and I am still getting faint lines on a pregnancy test. How long till the hcg is gone if you had a chemical did you see the doctor? Did you just let things run its course? I'm so confused