Where you can keep your will depends on your state's law, and perhaps your county as well. Most states do not authorize keeping a will in a county court house
before the will writer passes away. A few states or counties do. Your state/county might, because you say that the will was filed in the (county) courthouse registry. If you want to explore storing the will there, simply call them and ask if it's allowed.
However, I wonder why one would want to store the original of your will in the courthouse registry. The will writer wants his or her executor to have prompt access to the wilt upon death of the will writer. This may be more difficult to do if the will is stored in the courthouse registry. Generally, I think it's wise to store one's will at home, in a place where the executor can easily get it.