I just recently asked a question here about shoulder blade sensitivity two years post-op and it seems like the strange sensitivities do last for a while + leave permanent numb regions. I remember it still hurt badly for anyone to touch mine when I was around 3 months out too. It should start calming down
I also had lasting issues with laying back in bed. Again, I'm pretty sure it died down shortly after three months (the meds I was on killed my long-term memory of the recovery so I don't have a perfect recollection of when things happened). I slept on these pillows (Amazon link) for a long time and found they helped me lay back to sleep without injuring myself. They're expensive but saved me a lot of pain during the recovery period, and I still use them nowadays during bad pain days.
I was told silky pajamas help get in and out of bed so my friends bought me some so we'll see. For back pain, my sister bought me this rather expensive set of pillows to make sleeping in bed more comfortable https://smile.amazon.com/Avana-Orthopedic-Support-Comfort-Complete/dp/B00JMN5GWI/ref=sr_1_8?dchild=1&keywords=bed+wedge+pillow+system&qid=1619476970&sr=8-8
A bed wedge pillow system and a small lap table in bed was my absolute savior after my DMX. She will need to sleep on her back and slightly elevated for awhile and a bed wedge pillow system was a total lifesaver. This is the one I got and it the absolute number one thing I recommend post mastectomy. Avana Kind Bed Orthopedic Support Wedge Pillow Comfort System, 4-Piece-Set, Cloud/Camel https://www.amazon.com/dp/B00JMN5GWI/ref=cm_sw_r_cp_api_i_zCeuFbEF5MHR9
It may seem a little pricey, but I used it for nearly 5-6 weeks and was so comfortable every night. It was worth every penny, I would have paid twice as much.
Also, don’t waste money on all the expensive tanks and robes that are made to hold your drains. Just get a couple Home Depot nail belts for $0.79! They are perfect for holding drains and so much less fuss than pinning or paying $75 for a special robe.
This really helped me: Avana Kind Bed Orthopedic Support Wedge Pillow Comfort System, 4-Piece-Set, Cloud/Camel https://www.amazon.com/dp/B00JMN5GWI/ref=cm_sw_r_cp_api_glt_fabc_CD2815CSMCT68WBPFBPN?_encoding=UTF8&psc=1