My period was two and a half weeks late and I just got it two days ago. I have never had a late period I have always been on time and regular. I am currently not on any type of birth control. My last period I had prior to this one was two months ago on the 23rd of July and it ended on the 31st of that month. That same day I ended up having unprotected sex the 2nd of August I took a plan B pill. All of August I had no period and I finally got one this month on the 9th. Could I be pregnant? Or was that the plan B pill messing up my cycle? I have taken the Plan B pill before in the the past and I have never experienced this.