Erm, well you could ask the second guy if he CAME in you... (In england Nutted means being headbutted, and it sounds like you're being beaten up not having sex btw)
and if you end up preg its the second guy's maybe because you had a period!!
Be safe! :)
x
well there are precautions.
If you had a period on the 6th of September, and if you wind up pregnant, the father is most likely to be the guy with whom you had sex on September 20th.