hCg levels after loss

Pauline • Problem free pregnancies 15 YOB 💙 and 13 YOG 💗 Ttc for 2yrs. 1 Mc Jul 2015, 1 ectopic mar 2016. ICSI baby on board 👶
Hi ladies, 
Firstly, I'm sorry for your loss of you find yourself in this group.
My husband and I started to miscarry naturally last week. On the Monday we were told my hCg levels had halved from 1700 at 5 weeks. I have now gone down to 1-2 weeks pregnant on the clear blue test from 2-3 which took a full week. 
My question is, how long did it take to produce a not pregnant result from experience?