Hello well I had sex on May 8th, 2014. We used a condom and he pulled out way before he came close to ejaculating. So I got my period on May 11th-15th. But I have not gotten my period. I took a home preg. test on June 14th and 15th (both were negative) I went to the gynecologist and he did a urine preg test aswell on the 16th, which was negative. Again on the 17th I went to my medical doctor and he noticed I was late so he did a urine preg test too.. And it was negative. What could possible be the cause of my late period? Does stress really cause your period to be really late?