Dearie, no one can tell you that without knowing about your cycle.
Here is THE BEST help you can possibly get: "Taking Charge Of Your Fertility" by Toni Wechsler. You can get it at Barnes and Noble or Borders or Amazon. Read it. Pregnant next cycle. I mean that.
You will learn EXACTLY when you ovulate.
Now. If you want a guess...two weeks from yesterday IF you have a 28-day cycle. Ovulation TYPICALLY occurs 14 days before your period starts. So you can try calculating that. BUT...frequency can and does vary, which is why the book will really help you.
at 5:10 PM on Aug. 20, 2009