My Implanon Expired November 7 2015. I Had Been Having

My implanon expired November 7 2015. I had been having unprotected sex until December 25. I started my period December 26. Have been having mild cramps at night, I've been having on and off frequent urination, and some my smell has been really strong.. Could I be pregnant or is it the birth control? Thank you and haven't had my period