Period or implantation bleeding

Heather • so blessed to have my 2 beautiful children!
I unfortunately had a miscarriage 4 weeks ago, it was natural and I was 6 weeks. My hcg dropped to 0 on Dec 22. Still hurting but I still so badly want my baby. Anyways, I know I ovulated by all the physical symptoms and positive lh test. That was 13 days ago. We also had BD, i know i was told to wait but didnt. For the past 3 days I have had very very light bleeding. I took a pregnancy test yesterday and was negative. But why is my Af not flowing? Last time I had the same thing happen , a light period then negative pregnancy test then a week later I took a pregnancy test and was positive. So frustrating, I'm not sure if this is because of my miscarriage or I should try and test again in a few days. What do you guys think?