What Causes Abdominal Cramps,soreness Of Nipples And Delay In Periods?

Hi I got my tubes tied a year ago I am only 22 years and I have been sexually active with my boyfriend . I am starting to have. Low abdomen cramps. And my nipples really sensitive and tender even when I shower it hurts. My boyfriend notices I m being really hormonal and eating a lot. I m not a very over weight person and have a high metabolism. Plus no sign of my period I have it every 28 days can u please help I ve taken pregnancy tests and negative but I ve only started feeling these symptoms 3 days ago