Ttc after cerazette and noriday

Probably been asked a thousand times but have been on noriday since may then go changed me onto cerazett. Only took 10 days worth of pills as my and oh have decided to try for another. Stopped taking pill 3 weeks ago, Af is a no show Which has confused me as have always had my period like clockwork even on both pills. Now a week late. Having sickness, cramps, backache, headache and just feeling overly tired but keep getting bfn. Can anyone tell me what’s going on? Thank you x