Little cramps all over abdomen & swollen breast, I have feeling I am pregnant for the first time. Even there was a stiffness on my lower abdomen. But period came after 31 days. Usually its always 28 days from the past 6months. Flow is less than a regular period. Color is sometimes brown or light blood red. First day of period there wasI discomfort. My home pregnancy test result was negative. What should I do please suggest.