Positive pregnancy test after miscarriage

Hey ladies just wanted to ask those who would know. How long do you get a positive test after a miscarriage? Or how long after did u have one? I had a miscarriage oct.10 shortly after my DH and i have been BD although (tmi) ive been having variations of spotting and light bleeding. I took a test just to see if it would be negative so i would know if my levels had gone down or not but it was a strong positive. Ive been having headaches lately and still light bleeding. Is this a possible pregnancy or still miscarrying just wanted to hear some stories from you ladies