Is terrible breast pain with pills normal or is it better to go to the doctor?

I do not find pills called "Marcelin". You probably gave the wrong name and it is about the drug Marvelon. If so, please read on. Otherwise, please enter a valid product name. During treatment with Marvelon, breast pain and tenderness may occur frequently (more than 1 in 100 women, but less than 1 in 10 women). If the pain sensations are - as you describe - "terrible", then of course it is worth consulting a doctor. The gynecologist may first of all examine your breasts, as well as may suggest a change in the preparation if the pain is unacceptable to you. I enclose additional information: https://www.gdziepolek.pl/artykuly/jak-i-dlaczego-zglaszac-dzialania-niepozadane https://www.gdziepolek.pl/artykuly/antykoncepcja-hormonalna