With contraceptive, menstruation has greatly decreased ...

I'm 20 years old and I started using contraception. I have sex with my boyfriend. I took Ginesse 21 tablets three months ago and after I started taking it I feel strong headaches and the amount of blood has greatly decreased. Before it came 5 to 6 days and today in feathers 2 to 3 at most nothing comes and nothing comes when it comes in the form of a dark clay. This is normal?