The pressure can be relieved by making holes in that nail. This allows the fluid part of the bruise to seep out, which reduces the pressure and pain. The age-old technique has been to heat some rather sharp metal object to red hot, and hold it on the nail until it melts through the plate to the live nailbed beneath, where the liquid collects. You always feel when you get through. The lowly paper clip has been a favored device, which I have personally employed.
Doctors usually use one of two tools.
The tip is a wire that heats right up to 2,500 degrees and slickly sears through a nail. The other gizmo is a neat little battery powered drill that buzzes quickly and painlessly through a nail. The holes need to be made before the liquid gels. After about 24 to 48 hours they might not help much. Also, that nail likely will leave you after some months.