MISSED PERIOD?? HELP?

Could I be pregnant my LMP was 10/6/2016 I'm 3 days late I'm regular every month but last month it came 1 day late now I'm 3 days late  I took a home pregnancy test two of them came back not pregnant I ovulate on October 20th had unprotected sex October 16-18 plus October 23rd no symptoms I never been days late only like 1 day late.... so confusing please help? Is it possible to get pregnant the day of ovulation?? I heard before ovulation?