PCOS & Clomid

We've been TTC for nearly a year, and since I have PCOS I was recently put on Metformin & Clomid. Since my periods are horribly irregular, I was put on Provera to induce my period, then took Clomid. My first cycle failed, and I didn't get my period so they had to give me Provera again. I feel like last cycle I took my Clomid too early (I thought it was just going to be a light period like my one on August had been...now I think I had just been spotting because it got significantly heavier). I know I was spotting Sunday....but I'm not sure if yesterday was a day of heavy spotting or a light period. I know today is definitely a light to medium period day so if nothing else, today could be counted as Day 1. I'm afraid of getting my count wrong again and wasting another cycle, whether it be by taking the medicine too early or too late. I am supposed to take the Clomid on days 3-7. Anyone have any advice for the best way to judge the actual start of your period?