CD53, no AF and BFN

Hey everyone, sorry I'm new to this I've always been a silent reader and never posted. I am now on CD53.. And still getting BFN and no AF. I have been having symptoms of getting AF for over a week and have also had PMS. I came off birth control about February March time and had 1 long cycle but then ever since was straight into 30 day cycles. It's really frustrating me now because me and DH just wanna start trying again next month and AF is taking forever to show. We have been ttc since February March and noting yet. I have done 8 BFN the last being today. I spoke to doctor and he said can't do anything until missed 3 periods as I am getting BFN. Why is my cycle suddenly super long but getting all the cramps etc!? Any help would be appreciated. ta. Xx