Bleeding 2-3 days early on freya 28

Hey so i just started the 5th pack of freya 28. Doc said I should go on marvelon but the pharmacy gave me freya and gyne said that was okay. I saw my gyne a few weeks ago at the 4th month of the pills. I've always been beginning my period/withdraw bleed at the end of the last week of active pills but it got more full on when I started the placebos.

Anyway my doctor suggested I skip my period all together so I just started my 5th pack after beginning to bleed 3 days until the end of my active pills (4th pack(

Before I book another appointment with my Doc I just wanted to see what peoples experiences were. I'm worried because I had read abnormal bleeding means cancer. I also am concerned that I'm ovulating, like is my body somehow overriding the pill? I read somewhere if you have too low a dose you can still ovulate, is this true?