exactly how big is he ? i am a male and had the same problem with my girlfriend. it ended up just being a hormone thing for her. good luck
Pre ejaculation can cause pregnancy. It doesn't matter how much was in, or how long for, it can still be leaked and pregnancy can be a result of this. All you can do is wait and see if your next period shows or not. If not, take a test. You should be using condoms during any sexual acts, not only do they protect against pregnancy, but STD's too.