My upper back on both sides been hurting for 2 weeks and now the pain is irritating and worsening, what can it be?

Back pain: Upper back pain is in the thoracic spine. In general, most pain is muscular or tendinous in origin. Herniated discs in the upper spine are uncommon. Patients who are taking Prednisone are at risk for osteoporosis and compression fractures. An MRI of the thoracic spine can help make the diagnosis. See a neurosurgeon for evaluation and treatment.

Multiple possible: WIth your history of lupus, this may be a muscle inflammation issue, although if pain with breathing it may be inflamed pleura called pleurisy. Unlikely shingles as both sides of your back. It may also be your esophagus, which lies along your back and it may be in spasm from heartburn symptoms which may be a result of your medications. A simple strain would be better by now, rec you see MD.