Concerned and need advice

Has anyone that has been ttc or during early pregnancy ever have one breast become more firmer than the other?

My right breast is firmer than my left, mostly on the left side of my right breast.

That breast also sags more than the right one. They are both tender to the touch, but the right one hurts more so.

I don't have a family history of breast cancer. I am also 4 days late for AF, but the pregnancy test I took yesterday morning was a BFN. Just curious if anyone else has experienced this and what did it end up being.