I been having regular periods, now since after bc i don't have periods, its been over a year, can i just wait til my body start my cycle on its own?

No: You should see a doctor. You need to be evaluated and likely have blood work.

GYN-testing: You should definitely see a gyn and obtain a pelvic and pap smear as well as hormonal blood testing.

Amenorrhea: It's important to determine why you aren't menstruating. Are you too thin? Undernourished? Exercising too much? Anemic? Thyroid healthy? Once the cause is determined, the treatment can be decided upon. Medically it's best to menstruate at least 4 times a year. But the specifics will have to be determined by your personal doctor/.