I know you said you just started your period but I also see a LOT of misinformation here.
If you WANT to avoid pregnancy, you need to learn more about how your body works.
You ovulate (usually) 1 time per cycle. This usually happens 14 days BEFORE your period starts.
The egg lives only 24 - 36 hours. If you have sperm inside your body during that time frame, chances are very high that you will become pregnant. Another twist on that is that Sperm (semen) can live up to 7 days inside your uterus & fallopian tubes awaiting for an egg.
So, for example, if you have sex a few days after your period ends, and the man you have sex with has super sperm, it stays alive for the 7 days, you can get pregnant even if you have sex only 1 time!!
In your example, you had sex 5 days before your period was supposed to come. If you had a normal cycle, any egg that you released would've been long dead & the chance of pregnancy very very slim
at 2:03 PM on Aug. 22, 2010