Last month 10 days late, this month 16 days late w/ brown discharge, next day pinkish blood w/ clear mucus, next day heavy blood, today-day 19 nothing?

Irregular periods. 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.