Help!!!

So, me and my husband have been trying to conceive for about 8 months now with one for sure miscarriage back in February. My last period was July 18th-25th. I haven't had one since. I've had positive ovulation kit tests and fainted lines on pregnancy tests. I also had some very dark brown spotting, so I went to the doctor to get a blood test for my HGC levels and it was negative, what can I do next? I have so many symptoms but no BFP yet. Has anyone ever had this problem before?