Can you stop your period in a few hours for a day?

Not a constant flow: Your menstrual flow is actually not continuous. The cervical os (cervical opening is actually closed most of time) and thus preventing constant flow of your menstruation. When your uterus contracts, it forces the os to open and thus outflow of your period content. This happens many times during day. You see the blood all the time because "residual blood in vagina." consult doc. Good luck.