hCG levels three weeks after miscarriage...

Jenna • TTC#2. Have an almost 2 year old daughter. Miscarried at 10 weeks in April 2016. Chemical in July 2016.
I stopped bleeding a week ago and still have a suuuuuuper faint line on my pregnancy test. They drew my blood levels a week and a half ago and they were 48. How long til they are back to zero? I just want this to be over and my cycle to regulate. Does anyone else see the line? I was hoping I have line eyes since I have seen the line so many times during this miscarriage.