Hi, the pain in the upper back region following fall can be caused by direct pressure over the bones especially scapula
and ribs in that region or else may be due to muscle trauma. Damage to internal parts unlikely as there is no much abrasion or swelling outside. Injuries in these region usually take longer time to recover and rest to that part is compulsory for early recovery. You may need to consult a orthopedician or chestphyscian for x rays of that region. Wish u a early recovery.