Acupuncture, swimming, stretching and change in activities as these seem to be from repetitive actions that may possibly be aggravating past injuries or weaknesses from perhaps an auto accident years ago. It seems a common issue. Also you computer may be at a “wrong level” for your posture. Changing it can help. People at the Relax-a-back store are good at figuring out your perfect office posture (chair/desk/computer level and ratio) .
I have found the Theracane http://www.theracane.com to be most effective for me. It comes with instructions, including a diagram showing common trigger points. For me, my trigger points develop after the muscle is fatigued and/otr overworked.
I am amazed at the answers given! My suggestion, structure determins function and who better than a Chiropractor? besides he can be a beneficial provider. Second, it is your nervous system that is upregulated (sympathetic) untill you can down regulate it, the cycle will continue! Google, Musgrave wellness and performance and learn about (Reflexercise) it treats the problem not the symptom. Good luck!
It is difficult to speculate what may cause the condition without an assessment and inquiries about your medical and exercise history.
All the answers above may be possible ways to address your problem. My personal suggestion would be MELT (Myofascial Energetic Length Technique) which works on the fascia. I have seen encouraging results with upper back pain. I must confess, though, I am biased, since I am a MELT instructor.
What I recently did when I had pain that just wasn’t budging was a self-assessment. I did with myself what I would do with my clients: take pictures of static and dynamic posture and a video of the gait. As soon as I looked at all of it, I immediately got closer to the possible source. A very few exercises sufficed to determine the possible source of the imbalance, and I am now working on it.
Maybe that would be a way for you to make your own determination.