Can breakthru bleed happen anytime in cycle? it's happening now approx. 4 days before period and prospect of implantation bleeding worries me

Break through bleed: Pregnancy, stress, medication side effects, low body weight, high levels of exercise.Hormonal disturbances such as thyroid disorder, pituitary disorders..., peri menopause or menopause, ovarian cysts, medical conditions........There are too many potential factors. See a gynecologist for an examination and better diagnosis, .