Hi there Charlie, I can understand your anxiety and concerns. Now I am going back many many years, as I havr 5 children eldest 40 youngest 26 you didn't say if you breast fed your children. I breast fed all mine. I did have a very similar situation to yourself with a large unmoveable lump. Like yourself a quick referral to the breast clinic. I had a mamagram

plus a Scan in my case it turned out to be a milk ducts that had got blocked some how. So as milk was flowing as I was feeding where it got blocked it was just collecting in the same place because it couldn't get through apparently I was told after a few days it starts to thicken a bit like cheese. Sounds revolting. But it's continued to back up creating this larg lump I at the time just put it down to a gland of something. Anyhow why the doctor couldn't feel it was in the milk ducts because the lump was so large it had stretched the skin of the tubing so wide and high you actually couldn't fell the sorounding are of skin. I had the lump removed sent of for a biopsy which confirmed what the surgeon had said it was after he removed it. No signs of anything nasty at all. I have since been diagnosed with lung  cancer but it's so many years later. My only concern for anyone if they read my bio they would see. I had no symptoms as such to indicate cancer. I did cough up blood but instrimmin a lawn it felt like a stone flew up and hit me in the throat I coughed so bad because my gag reflexes kicked in. I genuinely thought I had cut the back of the throat I kept coughing up blood for 3 month. I could explain to myself why. Well every time I coughed I was opening the cut up every time I ate I was opening the woned up. Anyhow me chatting about lung cancer isn't going to help with your problems. I hope what I went through with my breat helped somewhat keep me informed my darling and the best of luck also the angels watch over you and your family and keep you safe