hi! I am 17 years old, and have been on birth control with a regular period for over 2 years now. My menstrual cycle has never been irregular especially since i started birth control. I had my yearly STD check up about a week and a half ago, and nothing was wrong. But about 3 or 4 days ago i realized my discharge was changing, getting thicker, browner, and more of it. im not expecting my next period for another week and a half. Can someone let me know whats up!?