I Am 7 Weeks Pregnant. The First Day Of My

I am 7 weeks pregnant. The first day of my last period was the 7th of June. I had sex with two different men a few days apart. The first man on the 18th I was not ovulating! He smokes a lot of marijuana and drinks a lot of alcohol. My question is how long can sperm live inside of a woman. I didn't ovulate until around the 21st which is when I was with the man I'm with now.