I've been on the pill for the past 6 months and this past month, ...

I've been on the pill for the past 6 months and this past month, my breasts have suddenly become unusually large and sensitive. Also, I came on twice in my last cycle - which has never happened before. I'm not sure if this is a side-effect (breast tenderness & size) or if I'm pregnant. I've also experienced a number of the other signs of pregnancy, but I'm not sure if this is my mind playing tricks on me. I've been in a serious relationship for about two years and I'm currently studying... so I'm really hoping I dont have anything to worry about - no babies on the way. This site is really a great help and my thanks goes out to everyone that has posted comments -- they have really reassured me about all the other side-effects I've experienced these past few months. As for the other side effects over the past few months on Yasmin - sore breasts, weight fluctuation, very painful periods at times, lack of libido, vaginal dryness, severe constipation (only once), head-aches, dizziness, nausea, extreme mood swings, excessive hunger at times, and many others.