That’s why I’m one of those that says that the Constitution doesn’t give us rights. Rather protects the god-given rights at the state can’t take away and that’s why there’s not an amendment regarding our right to murder.
Murder is not a right, natural, given by God, or anyone else. Self defense, on the other hand, is a right that exists exclusive or any document. The US Constitution limits the actions of government and specifically enumerates rights that were considered most important. Additionally, it does not limit those existing rights to those enumerated.
The framers of the Constitution intended to create a document to confirm those rights and limit government’s ability to interfere with them. It has worked reasonably well over the centuries, proving to be well written and durable.
Your argument is with the framers if you believe that you have the right to murder. I’m pretty sure they did not intend that or believe it.