Birth Control (Yaz) for two months-Very easy period before, breast tenderness now. Normal?

My doctor gave me Yaz two months ago to start taking for the birth control use itself. My whole life(20 yrs), I have had a very easy, short, light, painless cycle. I do feel blessed. I have finished one pack and I am at the end of the second pack. I've taken the pill everyday, same time (2pm). During my first period on Yaz for the about first time ( in 10 1/2 yrs), I had some pretty bad cramps. I was a little unsure why BC is prescribed for bad cycles when it gave me the worst one I ever had. I'm on here because for the last 3 days I am truly suffering from breast tenderness. They are so sore and sensitive, I just feel like somethings not quite right. Has this happened to anyone else? Is this normal? Thanks :) Sarah