Are you saying the “great and manifest day of the Lord” has already come? If the apostles and disciples at Pentecost were living in the “last days”, even more so are we.
Read the book of Joel again. (It’s pretty short.) What was Joel predicting? A chastisement of the Jews for their unfaithfulness, and afterward God’s salvation of and blessings upon the faithful remnant, with destruction upon those who persecuted them.
Then look again at Acts 2 where Peter says, in essence, “this prophecy IS being fulfilled.”