Ovulation post miscarriage

Hi everyone, I had a miscarriage at 5weeks and when I was in the hospital they told me my HCG was at 35 I tested about 5 days later and it was negative. I bleed for 6 days, I am now 2 weeks post miscarriage and I took a pregnancy test and a faint line was there, is it possible that this is a new pregnancy? Or is it just left over HCG?