I think I might be pregnant

I think I may be pregnant. There was a period of time that this would ensue absolute panic in me, but this time, I think I'm going to be disappointed if my test says negative.... am I growing up? Lol. But my reason why is that for the last week or so, I've had heart burn and nausea like crazy. I was supposed to get my period last Wednesday and I have not even spotted. (I am usually like clockwork) And don't laugh, but I feel like a sort of discomfort in my pelvic region. Not Pain, just discomfort. My husband and I almost always have protected sex, but I think once we did half unprotected and he put a condom on towards the end. Is it possible to get pregnant on precum? may be a juvenile question, but I'm not sure.