i think it varies for different people like what AnnieBrooke said because i conceived my son 3 days after my period :)
No. The egg falls once a month (once a menstrual month, to be exact), but it falls at different times for different women. The "typical" cycle goes like this:
Day 1 -- period begins.
Day 4 or 5 -- period ends.
Day 14 -- ovulation (the "egg falls.")
Day 28 -- last day of cycle
Day 29 (new Day 1) -- new period begins.
However, some women ovulate early in their cycle, and some ovulate late.
As you can see, in a "typical" 4-week cycle, the week you would be least likely to ovulate is the week of your period, although some women do ovulate right at Day 8, so I would not have sex at the end of my period if I was trying to avoid pregnancy.