MRI questions

in January I finally paid attention to a small dimple on my outer left breast and a slight flat spot on my lower right breast. Both become more pronounced when I flex, they have been around for more than a year just not sure how much.

After the initial visit with my primary she ordered an ultrasound which came back clear. She said that nothing really stood out as concerning to her that everything looked fine. I was still concerned because she mentioned feeling a slight lump on the left but nothing was seen on the ultrasound. In her clinical notes she wrote as follows (asymmetric firmness without discrete mass from 10:00 to 3:00 on the left breast. The right breast appears heterogeneous to palpation with indiscrete firm tissue, less organized than that of the left breast.). After extensive research I decided to ask for a MRI which was granted both by my doctor and insurance (Kaiser Permanente). However the order was only for a Unilateral Left Breast MRI?

I assumed the order would have been for both breasts to look for symmetry and what is "normal" compare to the other. And I mean you are already there hooked up to everything, like how much more work is it. And since this will be my first, to have a record for possible future evaluations.

All the information I've seen online regarding breast MRIs always shows both breasts, which is why I was confused when I saw the order. Never have I seen a single/unilateral breast MRI image, only when they zoom in on the final image to screen individualy and in more pronounced detail. Even when you Google them nothing really shows up besides general MRI info.

So I guess what I'm asking is if the MRI is only going to be of the left breast? Or is it going to be of both breasts with an emphasis on doctor interpretation on the left one?

If it was only on the left one and they found a anomaly what would happen next? Whould they do a biopsy first to look for malignancy, followed by MRI of the other breasts. Would the tech immediately scan the other one, or would you have to schedule another appointment to screen the other breasts and then have a biopsy? Also would it have to be an MRI biopsy?

Should I ask for a bilateral MRI, and would I have to be re-approved by my insurance because it is technically a different "procedures"? This is so confusing.😑😑😑😑

Another smaller probably insignificant question. I know MRI is magnetic so no metal is allowed but what about metal dental fillings mercury I think, are they a problem or no?