14DPO

14 days past ovulation with femara 2.5 days 5-9. I got a very positive OPK on CD 16. Is it too early to test? Glow is saying my period is in 3 days but it’s never accurate. I’m experiencing mild cramping throughout the day that comes and goes along with very sore dark nipples. Would it be a waste of money to take a pregnancy test?