clock position question

lefty37

I got a copy of my recent ultrasound with the positions of the masses found in my left breast. I had a biopsy done which turned out as a fibroadenoma at 1 o'clock in April..it is 4.5 cm from nipple. The new ultrasound shows a new one at 1 o'clock with a letter B that is 1.5 cm from nipple. It is similar in size to the one with the biopsy clip. My question is..that seems to mean it is on top of the first one? And if so is it possible that they missed this 1 x 0.9 x 0.6 cm solid mass on the first mammogram and ultrasound in April..And an ultrasound guided biopsy for the one deeper?.... or is it likely to be new? This was found in May on a second look ultrasound after birads 4 mri. Theyrare definitely 2 separate masses...4 in total. Thanks for any input.