Lab Results

K, ladies, so I gotta my lab results back, and I'm a little disappointed. My progesterone (taken on CD 18) was 4.3. Who really knows what that means, but I've Googled (shouldn't have done that)...some sites say anything above 2 indicates ovulation, some say it should be over 5. My concern (besides the fact I'm not sure I've ovulated) is it seems that low progesterone makes it hard to sustain a pregnancy. I have an email into my doc to discuss next steps.