So you are not ovulating before yo start your period?

Yes, you do ovulate before you start your period. You have to ovulate to have a period. However, the best way to calculate it is by counting ahead from the first day of your last period. Then you ovulate, then you have another period.

You normally ovulate, 14 days before your period begins, on a 28 day cycle, but it is possible to ovulate twice in one month without knowing. Read this site for more information:- Women can ovulate more than once a month - 09 July 2003 - New Scientist