If you MUST build something... then you need to relieve the pressure.
Heat the end of a bent paper clip (or a similar size metal wire) over an open flame until it is red hot. Use a pair of pliers to hold the paper clip during sterilization.
While it is still very hot, touch the tip of it to the injured fingernail. This is not a painful procedure for most people.
The heat of the clip will burn a small hole in the fingernail. It is not necessary to press hard on the fingernail to burn a hole.
As the paper clip is removed, blood should start releasing through the small hole. If not, retry the procedure until blood comes out and pressure is relieved.
..and presto. Back on the bench in a matter of minutes! I have done this multiple times. Or you can just wait.