I am 19 year old and I am concerned about my late periods. It's 32nd day today of my normal cycle and haven't got periods yet. I have had unprotected sex once during 4th day of my previous menstrual cycle. My boyfriend and I did use the coitus interruptus and to be on a safer side I took morning after pill within 3 hours of the sex. And lately I have suffering from stress regarding all this and I am also on antibiotic doxycycline which I discontinued for 5 days after taking the pill. Can you please suggest me what could be the reason for my late periods?