What is causing my irregular period? it has always been normal?

I am 19 and my period has always been regular, but in April it was two weeks late, and in May I had sex a bit rougher than usual and there was about 8 light days of a brown-pink discharge followed by my period a week early. Now two weeks later it seems as if my period has started again (again it seems to have been brought on by intercourse). Could you offer any explanations for this? Thanks
Answer:
im not quite sure but people are different im sure that if u get that brown/pink discharge that it can mean something big, so go see a doctor if it happens again..

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