I was due about the 12th or 13th of January but I was a week late so I had my period on the 20th but on the 27th I had unprotected sex. The next day, about 13 or 14 hours or so after the sex incident I took plan be one step. I was told it only lasts 3 days in your body and I was due to ovulate on Friday, Feb 1. I think I did still ovulate because of the change in discharge and stuff and I heard sperm can last in the body up to 5 or 7 days... So could I still have a chance of being pregnant? Please help...

Plan B doesn't always work. Yes, you could be pregnant.