Hi, I Am 25. I Normally Have A Strict 24-28-day

Hi, I am 25. I normally have a strict 24-28-day cycle and am rarely ever late. My last period started 21/2/16 and ended on 26/2/16. I should've began my next cycle on 16-19/03/16. Ive been having period-like cramps in my abdominal region for about a wk. Theyre not quite as strong as ones I normally have with my period, and yet are strong enough to be noticed. They are comparable to slight cramps you get a few days before your period, but it's been over a week and still nothing. Just slight cramping pains and a full pressure feeling. The cramping is at random times of the day and lasts maybe 30 secs each. Ive been thinkin my periods coming, and yet it hasn't yet. Ive also been havin a thick white discharge for the past few days, slight constipation. Any words?