My period is late as to i've been having weird symptoms what could this be ?

Pregnant or not: Do a pregnancy test! if negative; you could have an ovarian cystsd that can cause bloating and persistent pms symptoms. Stress can contribute to this as well (especially if you are worried about pregnancy). Abnormal thyroid or prolactin hormone the same. Taken antibiotics or had diarrhea on the pill? Do a pregnancy test. It could be positive. Start a prenatal vitamin if so! and see a doctor.

Uncertain: 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. Take a home pregnancy test to know.