You misquoted Jeremiah 31:31. It says, “The days are coming,” declares the L-rd, “when I will make a new covenant with the people of Israel and with the people of Judah.” Since this covenant is between the L-rd and the people of Israel it could not be the Christian covenant since that is supposed to be between the L-rd and all those, Jew AND gentile, which are under the Christian covenant.
Since the covenant between the L-rd and Israel is an eternal one, the one In Jeremiah supplements it, it could not possibly replace it. You make the common error of replacement theology.
If you believe that Jesus eliminated the need for sacrifice of any Temple then you have a problem. Ezekiel is clear that there will be a Third Temple, including sacrifices. That contradicts your theology.
What if Jesus is the third temple and he himself was the sacrifice? Since the old testament scriptures says a persons body is a temple of God.
He says he will make a new covenant with the people of Israel and the people of Judah, does not necessarily mean he won't share it with the rest of the world also.