Might be a dumb question

Melinda • Had 4 miscarriages in 2015 and had our rainbow baby December 2016
I MC on Sunday and my dr isn't checking my levels for another 3 weeks. I was only about 7 weeks along. I just took an opk just to see what would happen and it's completely negative. Like the second line is barely there. Is that a good thing? Does it mean my levels went back down? I've heard that opks will be positive when pregnant. Is that true? Should I keep testing with opks to see if and when I ovulate? I've heard of women getting pregnant right after a MC and pray we do.