How can I tell when I'm ovulating? My app says I did on the 19th but my CM was milky like and not exactly a lot of it... my cervix was high (too high to reach) but it's still high today and CM still the same? How do OPKs work... I tried them one month (after depo I worried I wasn't ovulating..) but I never got a positive, I got a line but it wasn't darker? When would I start using them if I have a 28-29 day cycle and at what time of day? Not clued up on ovulation and would really like to be as we're ttc in January.