I have just stopped taking loestrin2 24 on Dec 10 and got a period. I only bleed for 3 days. AFter that i had sex 2 days post ovulation and took an ovualtion test and it said i was fertile. A week later i started cramping and having lower back pain and have been feeling tired. And i never stopped my prenatal pills. I have taking hpt and they have came back negative 5 and 6 days before my period. I had a blood test done 5 days before my period and it was negative. I am wondering whats wrong with me.