I've had lots of upper and mid back pain with occasional pains down one or both arms and sometimes under the ribs almost a year. It feels like burning or pulling sensations with sometimes stabbing pains. I spoke to my doctor about it months ago...it's tension in the trapezius muscle which runs from your shoulders in a v - shape down to your spine above your waist. It still freaks me out a bunch but I've also started to isolate the causes (tense neck, bad posture and holding my smartphone for long periods of time). I carry my stress in my shoulders so this is a tough one to solve. But heat, stretching and one of those foam rollers definitely help.
When this pain started, it freaked me out because the pain was different than muscular pain in the lower back or other places. After almost a year, I don't have it every day but it's still a struggle.