Intercourse without protection, it was her first time, it lasted about minute, I am scared of precum

As I typing this, it's March 4, 2015. This is going to be a very long story. So to those who plan on answering my question, please read it carefully. On Saturday February 7, 2015, me and my girlfriend engage in sex without protection. It was her first time. Before I insert my penis in her, she gave me a BJ. Not sure how long it last. After that then I tried to insert my penis in her. The first time I tried to insert it in it didn't go in. I was struggling the first time. Then I briefly gave up and she gave me another BJ. I tried to insert it in again but I was still struggling. The reason why I had such a hard time because that day was the first time I had sex in 3 years so my skill was rusty. I try it again the third time and it got in (kinda). I don't remember but I think it went in. So I did my thing. The penis and vagina action only lasted about maybe a minute, I know it wasn't long, no less than 2 min. I did not ejaculate inside her. When I tried to put my penis in the third try, I wasn't turn on nor arouse. I did get an erection but my penis was a bit flimsy and not hard enough. Right now I am paranoid because I'm scared that my precum may have slip in. I am very very paranoid right. I ask my gf when was her last period and she doesn't know. She said she may have gotten it three or four months ago but again she wasn't sure. I ask her today on March 4 if she gotten her period and she said no. I am paranoid right now and need some sort of answer. Sorry for the long paragraph but I needed to be detail so I can hopefully get a better answer. Thank you for your time.