My boyfriend and i had sex and we're not sure if he came inside or not. some cum got on the lip of my vagina. most of the cum was out. pregnant?

Possibly: Withdrawal is never an effective form of birth control. Even if he is sure he pulled out before he ejaculated, there is a small amount of fluid ("pre-cum") that comes out of the penis long before ejaculation and it is loaded with sperm. I recommend that you get on an effective form of birth control, and consider being evaluated for the morning after pill asap.

SEX. PREGNANT?: IT IS HARDLY POSSIBLE TO BE PREGNANT FOLLOWING WHAT YOU DESCRIBE. HOWEVER, IF YOU ARE WORRIED, DO GET A PREGNANCY TEST. AND BE CAREFUL NEXT TIME(S)