Thank you for your complete and interesting response.
My gynaecologist told me that it was normal even he didn’t explain to me why. I must have gone yet but with all this stuff with the epidemic I barely leave home or make many appointments.

The thing about the 20 days wasn’t bleeding a lot along this period. I had a week widely bleeding, the rest of the days was only spotting.
And now after a week, again I’m with menstruation. lol! This time, pretty normal but I would like it gave me a breath because at this rate, I’m gonna be all struggling with it for the whole month.