What Causes Delay In Periods,cramps And Breast Tenderness?

I recently stopped the my birthcontrol, the nuva ring, after 12 years. I am on day 31 of my cycle and I havent had a period yet. I have had pink discharge, cramping and a week ago breast tenderness. I never missed a period when I wasnt on birthcontrol. I have taken several pregnancy test and they are all negative. What is going on?