WHY ARE MY CYCLES GETTING LONGER?? PLEASE HELP

Hi everyone

So I am TTC and I am in my 6th cycle. For my first 4 cycles I had 30,33,27 33 day cycles and then one 50 day cycle and now I am on cd 40 with still no period . I was on the pill and came off it 6 months ago. As you can see, my cycles were reasonable and then suddenly, really long ones. I have been doing digital ovulation tests and I am getting a surge each time , and I get all the symptoms of ovulation, just not getting pregnant. I’m not sure if stress is playing a factor? My dad is terminally ill and I’m a carer for him. But I don’t understand why my periods have suddenly done a massive jump. Can anyone else enlighten me ? Or has this happened to you?

Thank you 😊 .