Jo - Pen is talking about gestational age -a term doctors use, counting from the first day of your last period - which, of course, for most people, is two weeks MORE than the actual amount of time you have been pregnant. So yes, you would be 6 weeks gestational age if it's 4 weeks after ovulation and conception. And, since that was the absolute last time you had sex with him (right?) you cannot be less than 6 weeks gestational age (4 weeks actually pregnant).
And Pen is absolutely right, the odds of this being a viable pregnancy with no yolk sac and low HCG at 6 wks EGA is very slim. I simply meant to tell you that, if you have any discomfort with the decision to take the pills, and they did not see obvious signs of a tubal pregnancy, you can probably afford to wait a few days and retest your HCG before you intervene.
