Reason For Back Pain, Hard Stomach, Body Twitching, Frequent Urination After Taking Plan B After Unprotected Sex?

On July 14, I had unprotected sex around 3pm and had my period that same day around 10 something in the morning. The following day I got the Plan B One Step pill around 5pm and took it. Two days after taking it I had lower back pain and my stomach was starting to feel some type of way like it was hard and stuff. These symptoms last like a week or two, I took a number of things to get rid of them. Soon after, I started having body twitches like I feel like my pulse or it feels like a heartbeat all over. It could be my thigh, the right or left side of my stomach, my breast , even my neck . Eventually that stopped then my breasts starting to feel weird. They didn t feel sore to the touch however, when I inhaled in they felt weird. It has been and on and off thing now. I also have been having frequent urination , it use to be in the daytime, now its in the nighttime. I drank cranberry juice and water to help it and it did now, its back. Another thing too is that every morning I have to poop and I don t understand why, literally every morning. Also too my period was due on July 12, 2012 and it is now 9 days late. It is driving me crazy.