Tracking HCG to zero

Hate saying it, but after a d and c and chemical straight after I am desperate for my hcg to go below zero. This test isn't an frer it's a cheapie stick in the uk that just looks like an frer. It's still so strong and a week ago my hcg level had dropped from 68 to 50 - so I was kind of hoping it would be at 0 by now. I also took a cb digital last week that showed not pregnant and now one taken today saying 1-2weeks pregnant. Advice?