If he ejaculated near the vaginal opening it's always possible. not likely but it is possible. Just wait for your period. if it's late take a test.
i dont think so no you cant be pregnant if he ejaculated near you i really dont think dont worry.
the chances are pretty low that you would get pregnant. First for the sperm to actually reach the egg without being in the vagina is nearly impossible. Second if you were not ovulating it would make the chances even lower. Women only ovulate 1 day out of their cycles usually 14 days before the next one starts.