Trying for a rainbow after a D&C

Jennifer
I had a D&C 3 weeks ago. Unfortunately my baby had quit growing at 6 & 1/2 weeks & I didn't know it until my ultrasound almost 10 days after. We are trying for our rainbow baby but it's so confusing on when I will ovulate or when I might get a period. Last Tuesday my Beta was still 101 then last Friday it was down to 50. I took a home pregnancy test this morning & you can still see a faint line in the positive status. My questions are: when your HCG hits 0 are you supposed to ovulate then or that's when you will be expected to have a period? Or can you still ovulate with HCG in your system & if you can how low does the HCG have to be? I've been taking my BBT every morning & it's just been kind of up & down without much consistency so I don't know if that's my hormones or I'm just getting back to "normal" or what? Anyone have any advice? It's just frustrating that I SHOULD be out of my first trimester & instead I'm starting all the way over. Hopefully this time I will get my rainbow baby! Thanks for any advice