How long does it take for hCG to go down?

So my full question is how long does it take for hCG to go down after a missed miscarriage and a DNC.

Backstory on 8/21 my hcg was 50,091 then I found out on 9/4 that my little one had no heartbeat. On 9/10 I went through a DNC and my hcg then was 25,000. So it’s been about 2 1/2 weeks.

After the DNC all of my previous symptoms stopped, but yesterday and today I’ve been so nauseous. I was wondering if anyone else still had symptoms 2 1/2 weeks after? I definitely haven’t gotten my period yet, but I’ve been tracking the hCG going down by at home cheapies. The ovulation strips looked almost positive. Is this still from leftover hCG or do you think I’m about to ovulate?