Mid back discomfort?

 mine has been bothering me for well over a year now. i went for a massage and she said i had a ton of tension there, which was unusual. i think for me it's from still have huge boobs on a much smaller frame. my primary doctor also said something about it being from the muscles shifting after losing weight (that was in reference to a huge knot i have in between my shoulder/neck that WILL NOT go away, but i think it would be the same principle.

 Wow. So glad you posted this. I have that same exact pain to the point I can't sleep in my bed. I am up so much in the night with a heating pad. Today we went shopping for a new mattress bc I was sure it was that. I was talked into a 4k mattress and walked out before signing anything. It must just be part of the journey? 
Thanks for saving me 4000 dollars ;)