As I usually say in these kinds of threads, until you are told by an oncoplastic surgeon or breast consultant you have breast cancer, try not to worry about it. Most importantly though, don't google or doom scroll online. Believe me, no good ever comes from it and you'll only make yourself more anxious.
Sending all good wishes to you OP - fwiw, I'm four months post-chemo, two months post-radiotherapy, eleven months since mastectomy no. 1, and due to have a second in a few months time. You will get through treatment and surprise yourself with how you have coped with it all. And should you need chemo and you struggle/it makes you unwell, they will allow a short break if you ask.
Should you have BC, this book is really great, I recommend it. (I only read the chapters I needed to read, and only at that particular point of treatment. Lastly, breast cancer is sadly, a well-trodden path, although one that thankfully, is well-funded and researched. You'll be in excellent hands. Macmillan are hugely helpful, and if you are diagnosed with IBC or any kind of BC (or cancer full stop), call them and they will help.
Thinking of you ❤️