It's probably nothing, but might as well check

Okay, this might be long, I apologize in advance. I'm 30, and two years ago I found two suspicious lumps (one on each side) that prompted an ultrasound to be completed. Both were found to be fibroadenomas, with a follow up recommended after six months which they ended up backtracking on and never approving. The one on the right side was a "2.6 x 2.4 x 1.3 cm solid hypoechoic mass with circumscribed margins and parallel orientation to the chest wall." The one on the left was a "1.8 × 2.3 x 1.4 cm solid hypochoic mass with circumscribed margins and parallel orientation to the chest wall."

Fast forward, this year I've been seen multiple times by my PCP complaining about a cough, shortness of breath from talking/raising my voice, and a pressure/pain in my chest and throat. My o2 levels have been dropping strangely from just moving around, along with episodes of tachycardia I've needed a beta blocker for. I've had multiple chest X-rays done that were all clear---until the one I had last week on Wednesday, which showed an area of "abnormal infiltrate in the upper medial lungs." Doctors assumed pneumonia, put me on antibiotics that didn't work, and then ordered a CT scan.

This is where the results become relevant to this Reddit, thank you for making it this far. The CT (w/out contrast) revealed a 2.1cm mass in the right medial breast. I asked if this was the same one as last time, since fibroadenomas can shrink and even disappear overtime, and they said they couldn't be sure without a mammogram, which I have on Friday. I had to fight with the imaging center just to get it scheduled, though, because they listed me as having no symptoms.

The thing is, things HAVE been weird. I've always been a little lopsided, but I noticed about eight months ago that my right side is now visibly bigger (at least, to me). I asked around about it, and others said that it didn't look concerning, but now it's to the point where my right side is significantly larger, and I'm spilling out of my bra on that side while my left side isn't even big enough to fill the cup. I thought it was maybe weight gain, but I don't know. I've also been having weird skin changes on the right side (red, pus filled lumps that are extremely painful, pop, and then the redness stays behind, leaving kind of a polka dot pattern on my skin). This is now happening on the left side, too, but the bumps are significantly smaller. I thought this might be a weird acne thing since I have very oily skin, but again, I am now second guessing, especially since the ones that popped months ago are still red marks on my skin. I've also been having a lot of tenderness, but I've also always been sensitive in that area, and now I'm overthinking things.

Wearing a bra at all has also become weirdly painful. I'm always sore after in my back and chest, and I've also had episodes of shortness of breath that I've linked to wearing a bra at all, as the episode will resolve after I take it off.

There is no history of breast cancer specifically in my family that I know of, but my uncle has had cancer twice (just different varieties). He responded to treatment and entered remission both times.

I think my main question is: what should I ask at my mammogram on Friday to ensure the proper steps are being taken moving forward? I know they probably found the same fibroadenoma as last time, but what should I be keeping an eye out for so that something doesn't get missed?