My period is 12 days late and i have a few symptoms. i have took several home urination test, women clinic urination test and all test were negative.

Doesn't sound like: You are pregnant. Reasons for missed/late periods: low body weight, obesity, marked weight ^ or v, over-exercise, endurance athletics, breast-feeding, ^ stress, illness, eating disorders (bulimia or anorexia), anovulatory cycle (no egg released), travel, hormone irregularities, drug use, meds (i.e., birth control) or medical problems (i.e. Pcos). #1 reason is pregnancy.