It's worth giving the physical therapy a try since it does help some people. I tried it for a few sessions about 6 months after my double mastectomy, but it didn't help me with the tightness in my chest, muscle spasms, shooting pains, etc. When I did the physcial therapy it was the only thing I could do that day. Afterwards I was in more pain and unable to do other basic tasks like prepare meals, take a shower, feed my service dog, wash dishes, etc. so I stopped the therapy because I had to be able to function. For me the combo of muscle relaxer and pain pills combined with trying to be as active as I can and moving around as much as I can each day works best.

I do have midsternal pain, tingling, shooting pain. When I take a deep breath at times it feels like I can not get a deep breath. I feel tingling on my chest with deep breaths. Oncology recommended PT.

I have had post mastectomy pain syndrome (PMPS) since my double mastectomy in 2017. The AI response to this breast cancer side effect is lacking quite a bit as it seems to be talking more about heart attack symptoms than PMPS symptoms. I don't personally experience shortness of breath from PMPS, although I do have shortness of breath due to heart damage from the two times I've gone through chemo. I do however end up with pain sometimes when I breathe, but it isn't a lung thing. What happens is my chest muscles spasm and get really tight, my scar tissue is tight, plus I will get shooting nerve pains which makes it painful to breathe in and out from a muscle/nerve point of view. I also literally feel every single breath that I take, even when my muscles and nerves aren't acting up which doesn't hurt, but it is an uncomfortable and weird feeling. This is due to the tightness in my chest from muscle damage and scar tissue from multiple surgeries and has been tightening up more during the last month since I finished up 20 doses of radiation. If you are having shortness of breath/trouble breathing you should talk to your doctor and see if they can figure out what is causing it. If it's more of a muscle/nerve thing like I described you may need muscle relaxers and/or pain killers to help deal with the physical discomfort.