I had unprotected sex last month (9th September) and took the I pill within 24 hours. I got my period on time i.e. On September, 15th even after consuming pill but the cycle was shorter than the usual. This month my periods were due on 16/17 and I am 8 days late. I even took the home pregnancy test which was negative. Is it too early? Do I need to repeat the test again? Or is it due to pill. I am also facing mild headache occasionally. Kindly explain in detail. Thank you.