I am about 9 days late now. I had my period on September 1st and ended September 6th. Again, I had it on October 2nd and ended October 8th. I'm supposed to have my period on November 2nd-4th but it hasn't came. I had unprotected sex during the 14th&15th of September and now had it sexual intercourse again on the 4th-6th November. My cycle is regularly between 29-31 days. I have been stressed these few weeks but is that the cause????