Plan B imbalance or Pregnant? Nervous HELP!

My girlfriend and me were trying to have anal and my penis slipped out and some precum might of touched her vagina wall(no previous ejaculation). We are both virgins and this freaked us out so 12 hours later she took the plan b one step. two weeks later she started having really heavy bleeding for eight days so does this mean were in the clear?

We both thought there was no chance then shes having all kinds of PMS/Pregnancy symptoms that she normally doesn't have but i thought maybe its just from the chemical unbalance and its just getting her body all out of whack.

Should we be worried or no?

[KTowne]

First of all, it's highly unlikely she was even pregnant before she took the plan b, and plan b can be very strong on a cycle, it can cause irregular periods, spotting, cramps, etc. I'm sure she's not pregnant, however, in order to protect you and your girlfriend in the future, you need to be wearing a condom, to not only protect from pregnancy, but from std's too! Good luck!