Can OPK pick up HCG as well as LH??

I miscarried 6 weeks ago, still no period. Had purchased opk for when we started ttc again. Last week I took one just to see and it was positive, another one today was positive also? Is it possible that I could be actually pregnant and it is picking up HcG? I just don't see how I could be getting positive for ovulation for a week? Top test is from last week, bottom test is from 5 mins ago. Last weeks test was positive before the 3 minutes!