Not sure about the pump but my advice is not to put your finger over a hi pressure air source and pump it.
The most serious damage that can be caused by compressed air occurs when air is blown in under the skin, for example via an open wound. It can lead to an air embolism, in which air bubbles are pressed into the veins and transported along the bloodstream. When the air bubble reaches the heart it causes symptoms similar to those of a heart attack. When the air bubble reaches the brain, it can cause a stroke. This type of injury can be directly fatal. Since compressed air usually contains small amounts of oil or dirt, severe infections can also occur if the compressed air enters the body.