Had unprot. sex, took plan b on my third day of birth control on the 3rd month (2nd month missed a pill because i lost it, bleeding 2 weeks) pregnant?

Pregnant?: Not sure what you meant with the dates? Are you saying that you had been on ocs for 3 cycles, had 1 unprotected encounter on day 3 of the 3rd cycle (having missed 1 pill - which one?) during the 2nd cycle, and took ec right after the encounter, experiencing 2 weeks of bleeding soon thereafter? Ec itself can cause prolonged bleeding and if my assessment is correct, you probably weren't pregnant.