What happens to pressure if it is concentrated into a small area?
The force applied increases.
Since pressure is defined as Force/Area, a decrease in the area over which force is applied would result in an increase in pressure on this area.
This can be seen with water hoses, which produce a leisurely flow of water when unblocked, but if you put your thumb over the opening, water would spew outwards. This is because moving your thumb over the opening reduces the area over which force is applied. As a result, pressure increases.
This principle is also how many hydraulic systems operate, like the hydraulic press. This pressure, force, and area manipulation has become an extremely handy tool for technology.
To answer your question directly, though, pressure concentrated into a small area is the same as pressure concentrated into a large area. By definition, pressure is Force/Area, so no matter how much area you have, it will still "feel" the same.
What really changes is if force were concentrated into a small area. A highly concentrated force will result in a very high pressure.
Pressure: the force per unit area exerted by an object against a surface with which it is in contact.
#"Pressure" = "Force"/"Area"#
If same force is applied once on smaller area and then on larger area, the smaller area feels more pressure than the larger area, since