Melatonin and BC

Kristen • Engineering major trying to survive college
Hey all,
I started the pill (Sprintec) about a month and a half ago, and my physician told me natural supplements, such as melatonin, can negate the benefits of BC. However, I'm a college student and still have yet to maintain a good sleep schedule, and sometimes pop a melatonin after a night of late studying to guarantee sleep before class. If I'm not sexually active and taking the pill to help regulate cycle timing, how much should I worry (if at all) about the occasional sleep aid? Thanks!