I had unprotected sex with my g.f for the first time because she kept me insisting me during the last 3 months. I was reluctant at first because I know the after-effects of unwanted pregnancy. I told her I don't have a condom but she told me that the last 4-5 days prior to her due date of menses is safe (I also knew this since I was a science student during my college).. still then she insisted and out of our shared love I did it. I didn't ejaculate inside and I pulled out mine way before I had the urge of ejaculating. She told me she is expecting here period on 29 or 30 of this month. i.e. April 2013. Till today she is yet to get her periods.. which has made me worried. Could you please clarify this for me whether she is safe from pregnancy?. I swear I won't repeat this again in life.

'the last 4-5 days prior to her due date of menses is safe'

No, there is no 'safe' time. A woman can get pregnant any day, even during her period. The odds are lower, that's all.