34 days delayed on my period, negative pregnancy tests, what could be the reasons? what to do to jump start my period? thanks

Missed period: Reasons for missed / late period include: an anovulatory cycle in which no egg is released, marked v or ^ in weight; eating disorder; over-exercising (endurance athletics), travel, significant illnesses, oral contraceptives ; other meds, illegal drug use, breast feeding, hormone imbalances and medical problems (i.e., pcos). If you miss period x 3 cycles, see gyn or sooner w sxs.Progestin can help.