I need to know in order to obtain peace of mind!!?

My my girlfriend and I had protected with some before I put on a condom, but it was just kidding and so on. I'm guessing I had a little pre because it always happens in little amounts. But I never broke her hymen, and even came. I wore a condom and made sure it was on good. It was like a week or so before her planned period, I dont know if that has any effect. Anyways. She never got her period last week and we are kinda freaking the hell out. I didn't have any sperm in my urethra for the pre to pick up, and I pee'd multiple times that day during cl. So whats the problem? She has been stressed out over ACT's and finals and worrying about this as well. She does track for an hour and a half after school everyday and swims competitively at night for about 2 and a half hours. I mean, it boggles my mind because I was careful, used a condom and didnt even ***. Also, when are the days that she is really easy to get pregnant? Thanks, a lot. I'm not ready for a kid, nor is she. We get good grades in school and are a great couple, this cant be ruined by a kid, not yet. Any links or anything would be good, i'm willing to read. Maybe we'll reconsider having . I definantly learned my F**king lesson, haha. THanks guys!!!