Hi I'm 22 have healthy son who's almost 3 years old, my problem is my periods are coming later each month they used to always be every 28 day's. But for the last 7 months they have gone from 28 to 32 then 36 and now I'm on day 40 still waiting for this months. There is no chance of pregnancy as I haven't had sex for around 8-9 months now. Does anyone know what could be wrong please?

Periods can be late a lot of the time,it can be coursed by almost anything:
Stress is the main one,Its hard for anyone to say. I strongly suggest you go to the doctor,the doctor is the only one who will know what's wrong,
Sorry I couldn't help that much try not to worry