I Have Done My Mammogram 10 Moths Ago. In April

I have done my mammogram 10 moths ago. In April I feel like I have something in my breast I went to the doctoctor and the did again mammogram and ultrasound and they said there is nothing just fibroglandular tissue that is not dense. And now this past three weeks I feel my side of breast kind of sore and now I can feel it most all ove my breast. Can you kindly advice? Thank you