I had sexual intercourse on the 5th day of my periods. i took ec pill on 7th day.have bleeding from 13th day to 15th day, am i pregnant?

Sounds like no: We would suspect pregnancy from the lack of periods not from increased vaginal bleeding. Most likely you are just having irregular bleeding after taking emergency contraception which would disrupt the normal hormonal balance. You can always check a home pregnancy test though to be sure. See your doctor to start long term birth control and prevent this in the future.