Talk to Sexologist on Periods Spotting Issue

Last month I had unprotected sex and I took birth control. The first birth control I took was in July. In September took ecp again and I had an irregular menstrual cycle like 5 days before the normal date and I lasted for 8 days. Now I am facing very light period spotting issues since two days it's a pink shade but rare sometime it stopped. What does it mean and when will I experience my normal period? Is it serious or not