Poor posture is the commonest cause of back ache. The common causes of middle back pain are overuse, muscle strain, or injury to the muscles, ligaments, and discs that support your spine. Any condition exerting pressure on the spinal nerves can cause pain. A herniated disc, degenerative disc disease, spinal stenosis are few other possibilities. Schedule an appointment with an orthopaedician. A complete physical examination and tests like X-ray and CT scan to look for any injuries may be helpful. Do keep us posted.
Best luck and regards!
Thank you so much for answering my post. I will definitely schedule an appt and as soon as I know something, I will post again. Thank you!