If she has a perfectly accurate 28 day cycle with ovulation occurring around day 14-16, then she might have been on the tail end of being fertile. So she might have been a little fertile, but not at peak fertility.
Keep in mind, however, that ovulation is a very funny thing. Most women have no idea when they are ovulating. Many women do not have the typical 28 day cycle with ovulation occurring occurring around day 14-16. That pattern is sort of the standard ovulation model, but ovulation and the female cycle does not run like clockwork. That means anything is possible. Some women even get pregnant when they have sex during their period!