I had sex on the 11th ovulated the 11th-13th and took the pilll on the 14th right before the 72 hour mark...could i be pregnant?

Maybe not, but...: Plan B and other emergency contraception pills can alter the menstrual bleeding for the cycle in which Plan B was taken, and sometimes the next cycle too. One should be sure to check a home pregnancy test about 3 weeks after sex, because Plan B works most of the time, but not all the time. It is more effective at preventing pregnancy when taken right after sex but should still work 72 hours after.