Hello thank you for your query. There could be many possibilities for this kind of bleeding. Firstly, as your period was late, and then scanty and abnormal, it could be indicative of an early pregnancy, a failed pregnancy or an ectopic pregnancy. Apart from that, thyroid disorders, high prolactin levels or polycystic ovaries can present with such a picture. Stress, anxiety, rapid fluctuations in weight, travelling, emotional trauma - all can cause such bleeding. Being on hormonal medications could be a cause. You need to consult your gynecologist for exact diagnosis, as just by reading the description, I can only list the possibilities. Take care.