Opk? Any advice?

I took an ovulation test about 3 weeks ago and it was postive. We BD'd but I got a negative pregnancy test today. I took an ovulation test as well and it's postive. I had a miscarriage about a month ago. Why am I ovulating so soon. I'm so confused. Please help! BTW my numbers were at 0 when I got my first positive OPK 3 weeks ago.