Yes,semen can live 3-6 days in the body.
Also, as a side note, Plan B is only meant to be used in an emergency and not as regular birth control. It's not advised to be used more than twice in a year as it can mess with your fertility and cause problems.
Otherwise, your best bet is to wait and see if you are pregnant, and if not...get on birth control. Good luck.
Okay, so you had unprotected sex today? Because if you did, you can get Plan B from the local pharmacy. It's meant to be used up to 72 hours after unprotected sex and it helps to keep sperm from fertilizing an egg or keep an already fertilized egg from attaching to your lining. It isn't an abortion pill, so if you're already pregnant, it won't abort and it is only 80% effective.
If it's been longer than 72 hours after the incident, then you'll have to wait and see if you're late for your period. Condoms and birth control are necessary if you don't plan or want to conceive. Anytime you have unprotected sex you always have a risk of getting pregnant.
You are fertile 5 days before and a day after you ovulate. So yes, there is a chance you could get pregnant.
If you have unprotected sex, there's alwaysssssss a chance of getting pregnant. Of you don't want to get pregnant, wear condoms and get on birth control.