How soon after cervical mucus will i ovulate?

i had the stretchy/fertile mucus 10/19.. but i bd 10/18 and 10/20 (also a cple days before and after that date i heard it's best to have every other day so the guy's sperm can build up and be more healthy). my average cycle is 30 days and i'm never late except last month i was 8 days late and i'm a little confused on when my period will due since i was soo late last month. (lmp 10/6). i do know that my period will come about 2 weeks after ovulation if conception did not occur, so approximately how long after the stretchy mucus did i ovulate?