There's no way to know. The average is around 14 days after the start of your period, but it really could have been any time from a few days after to much later.
If you have a regular, 28 day cycle, you typically ovulate 12-14 days after your period starts. You probably ovulated sometime in the first few days of November (November 5th would have been 14 days).
For a reference, I was tracking ovulation because I have long and irregular cycles (30-36 days), and I ovulated October 31st with a LMP on October 13th, and my EDD is July 20.
Look up due date calendar on google. They are an average of 28 day cycles, but they also give an estimated conception date. I don't remember what it was called, but there is one out there that you can adjust your cycle days from 28 to however long your cycle is. Its not certain, but it may give you a date near when you had sex. (Mine says I conceived Oct. 23. That was a day dh and I had sex. Its possible I conceived from that day, or from sex we had a few days earlier since it can take a few days for sperm to get to egg.)
I was pretty far along when I found out I was preggers (I have an irregular period and it's normal for me to skip some months). OB estimated DD based on baby's measurements. I had him calculate the conception date for us and I think he was pretty spot on. Guess we will never really know though.
Re: Ovulation?