29 and Concerned

Over the past year, my left nipple has slowly inverted. It was never inverted before and is at the point where it doesn't come out at all. I have also been having some pain under my arm pit area of that breast. Both of my Grandmother's have had breast cancer...One in her 30's and one in her 60's. I had a mamogram and sonogram which actually showed a cyst in the right breast, the one with no noticeable changes. I just got an MRI done yesterday and my doctor called today and said she didn't see anything in the left breast (the one with the suddenly inverted nipple and pain), however she noticed something questionable in the right and wants me to go back in 6 months. Has anyone experienced any of the same symptoms that eventually led to breast cancer. I am very concerned about these sudden changes to my left breast with the history of breast cancer in my family.