The type of pain described by you is more consistent with a mechanical back pain
, where in with movements like changes in posture or breathing, coughing
and sneezing the pain is aggravated. Cough and sneezing cause the muscles to contract as a protective mechanism around the injured part and hence the pain. This is more common with small fractures or a herniated disc. So, I would advise you to consult your doctor at the earliest to rule out a fracture. A plain x ray may show up a fracture.