concerned!! anyone experienced this?

I had sex on the 18th. he took of the condom and didn't cum inside of me, but i still took Plan B 2 hours later. I had my period on September 8th - 13th and I was apparently ovulating according to eve it was marked green so I was glad I took Plan B asap. BUT 2 days ago I stared bleeding a lot like a full on period and I'm still bleeding.. is this bad? am i not pregnant? is this a period? I was suppose to get my period on Oct 7th so I'm confused..