What do it mean when you start your period then stop the same day?

Not much: Irregular periods are one of the most common problems obgyns treat. If this is one time problem it usually resolves on its own. If this is a recurring problem you should be evaluated. Infections ; hormonal changes can cause spotting. If there is a concern for pregnancy then do a home pregnancy test . There are many options available to help regulate the menstrual cycle. Schedule a visit.

Wait: Sometimes ther can be variation in the length of your cycles. It may restart or you just may have a short cycle.