Is the occurrence of withdrawal bleeding from the 5th day break a cause for concern?

I take Microgynon 21 birth control pills. At the beginning it was 12 o'clock and I was getting bleeding on the fourth day (on the leaflet it says that you get it after about 2/3 days, so the fact that it gets the 4th did not surprise me then). After a few months I moved to 22 o'clock and I get bleeding on the 5th day and it worries me a little, can this be the case for me? We do not use condoms with our partner, we have regular intercourse.