Diagnosed to have PCOS and had unprotected sex on the day of expected period, but there is no period yet. What is the chance of pregnancy?

Hello doctor,

I was diagnosed with PCOS last year. My doctor told me to take Diane 35 for four months. I stopped the pill two months ago, so my last period was on the very next month of stoppage of the drug. The periods was shorter and had no periods the next month. However, I had brown spotting or bleeding from day 27 up to day 34. I had unprotected sex on the day I was supposed to get my period. What are my chances for pregnancy? I consulted another gynecologist and told her my condition. I did an ultrasound, and my uterus already appears normal (according to the doctor, less visibility of my PCOS condition). I consulted last week, and she prescribed me Provera 10 mg for five days, twice a day.

She said the cause of missed period is because of hormonal imbalance or adjustment. She advised me to retake Diane 35 for next 12 months once I get my period. By mistake, I had Provera in the morning and night instead of taking the two tablets before bedtime. She said the Provera is supposed to make my period come. It has been seven days since I started using Provera but no signs of period. I was on medicine for cough and cold for five days. I am also going through emotional stress as of now mainly because of missed period. Could that be a factor for late period? I took a pregnancy test, but the result was negative. I tried two different tests and both came out negative. Please help.