No period on Day 30 of Clomid - Persistent Corpus Luteam?

I am currently on Day 30 of a Clomid cycle - 100 mg, days 3 thro' 7. I had a blood test for Progesterone & HCG on Day 26 (atleast 10 DPO) that revealed ovulation, but the HCG test came back negative. I have had brown spotting off and on since Day 27, but no "full-fledged" period yet. Could this be an miscarriage? Was the pregnancy test taken too early and is there a chance that I could be pregnant? Could this be a case of persistent corpus luteam? What are the chances of persistent corpus luteam even if ovulation has occured in a cycle? Prior to developing PCOS in 2002, my cycles have been 28-30 days before. I began having "regular" cycles - 28 to 30 days long, only following a D&C in Dec, 2002 following a miscarriage at 9 weeks.

Thank you in advance for your time and advice.

[WinterAries]

I have no idea what all that stuff meant but what I did catch is that you think you may have taken the pg test too early.  With my son I didn't find out until I was 8 weeks even though I had done home HPT a least 2 times.  With my daughter I didn't find out until I was almost 12 weeks pregnant.  I found with her by accident.  *tried to go into the marines* but, they said "uhhh, after you have your baby..." I knew I was pregnant with my son, with my daughter I was clueless.  I spotted off and on, just like you, but I thought it was stress.  If you're really really not sure, get a blood test!  In my case right now, I'm not sure of those things anymore but in the past 2 times, they worked so good luck!!