Period help ?

My last period started 5th December had it for around 6 days , before birth control I was normally 28 days so would have been due 2nd January but it’s never arrived , going by this am 23 days late so basically cycle day 52 , however I stopped taking birth control a week before Christmas! Family planning says a would be fertile straight away. I have added my cycle to 35 days would still be late then 42 days which means even later! Basically not had a period in 6 weeks, is this normal , took pregnancy test this morning and negative but maybe too soon to tell if pregnant or not , I had watery discharge 12th January & spotting when I wiped at the toilet on the 14th part from that nothing expect mild cramps etc keep thinking its coming & never does, so maybe I was ovulating, my question is can you skip a period after stopping birth control then just fall pregnant without even having a period?? Gonna phone drs Monday if it’s still not arrived 😞