This has never happened before

I need a little reassurance. My partner and I were having sex and we went to change positions. When he pulled out the condom stayed in me. It was easy to get the condom out, and I made him put a new one on before we continued. I'm just worried that I might get pregnant from this, as he had pre-cum on his penis when he pulled out. Has anyone else ever had this happen? What was the end result?