Ovulation

Don’t think I’m going to be ovulating this month, why window started from 31st Jan - 5th Feb according to Glow but I don’t really know when I ovulate and I’ve not had any sticky creamy discharge. Sometimes I do it that and also like brown in it, which can also mean ovulating. I’ve had twinges in my left ovary which can also be a sign, I don’t have a right ovary that was removed 3 years ago. Why is it so hard!