If you have been having sex there is always a possibility of pregnancy. If you feel that you may be pregnant you should take a home pregnancy test and/or see a Dr.
Pregnancy Without Penetration.
It is not impossible, but highly improbable. Even when ejaculation occurs inside the vagina, and even when the woman is ovulating, there is still, on average, only a 7%...
It is possible; it is not specifically that you are now anti-social but that you have more hormones interfering with your "usual" system. You may feel the need to have more personal times; or even...