Can Mercilon Contraceptive Pill Cause Bloated Stomach And Nausea?

Hi I have been taking Mercilon contraceptive pill put just over a week now. I have a very blosted stomach and waves of nausea throughout the day. Are these symptons just my body getting used to the drag. I am am also woried about wieght gain as I also feel to be carrying excess water or putting on weight with it.