Hi, I was on birth control pills. I had a sex on the 11.12.2013,unprotected and on my period, I stoppwd bleeding a day later. I had a tiny bleed after and it stopped. I since stopped taking the pill, tge last time I had sex was the 11.12.2012, and up till now I haven t had a period, I took a pregnancy test , came up negative. I have tummy cramps and is very thirsty!. Why is there a del ay in my period?