Does dyspnea require actual shortage of oxygen or does it include the believed lack of oxygen? can it be ruled out if oxygen supply 94-97%?

It's a symptom: First of all, the body compensates for bad lungs by increased breathing rate which is when people feel dyspnea. second, you can have the feeling from increased pulmonary blood pressures but without problems with oxygenation. These are some lung causes, there can be metabolic causes (cyanide or carbon monoxide, or acidosis, etc), and psychological causes.