Hello. I Had Unprotected Sex The Guy Pulled Out And

Hello. I had unprotected sex the guy pulled out and I took plan B the same day. I had my period on August 19th and I had unprotrcted sex on august 28th. After taking plan B that day I got my period two weeks early on September 3rd. I have taken four pregnancy tests since that time and they have all came back negative. My period have always been regular so I'm still worried. Should I be expecting my period soon? Or is my cycle just all messed up?