1 day period? What does this mean?

Natasha

Hey ladies I normally have very regular periods and they always come on right on schedule and last 4-6 days. This month my period “started” on the right day but only lasted one night and there was barely any blood. I did not bleed at all after that. Now i am not on birth control because it messes with my hormones way too much but i have been doing natural planning to avoid my ovulation cycle. Is it normal to have a 1 day period every once in awhile? Who here has ever had one and realized they were prego