What Causes Severe Pain With Brown Discharge After Stopping Crisanta Pill?

im 24 years old,5ft 4 inches and im 65 kgs.i have been using crisanta for the last 6 months for endometriosis ,diagnosed on the basis of symptoms.2 days after i stopped the ocp i had severe cramps and brown discharge so i started the medicine again.its been 2 days since and there is no relief and the brown discharge has become thick.HELp