Dear Trevor:

The short answer is that when we die God gives us his Particular Judgment. In the Particular Judgment the individual is judged by Christ of a moment after death (Hebrews 9:27). This is the judgment that determines our eternal destination to heaven (perhaps through purgatory) or to hell.

The General (Last or Final) Judgment is the final judgment by Christ of the human race on the last day at the resurrection of the dead (Matthew 25:34, 41).

The Catholic Encyclopedia explains in more detail:

The Roman Catechism thus explains ... besides the particular judgment of each individual, a general one should also be passed on the assembled world: "The first reason is founded on the circumstances that most augment the rewards or aggravate the punishments of the dead. Those who depart this life sometimes leave behind them children who imitate the conduct of their parents, descendants, followers; and others who adhere to and advocate the example, the language, the conduct of those on whom they depend, and whose example they follow; and as the good or bad influence or example, affecting as it does the conduct of many, is to terminate only with this world; justice demands that, in order to form a proper estimate of the good or bad actions of all, a general judgment should take place. . . . Finally, it was important to prove, that in prosperity and adversity, which are sometimes the promiscuous lot of the good and of the bad, everything is ordered by an all-wise, all-just, and all-ruling Providence: it was therefore necessary not only that rewards and punishments should await us in the next life but that they should be awarded by a public and general judgment."

The (Last) judgment will embrace all works, good or bad, forgiven as well as unforgiven sins, every idle word (Matthew 12:36), every secret thought (1 Corinthians 4:5). With the exception of Peter Lombard, theologians teach that even the secret sins of the just will be made manifest, in order that judgment may be made complete and that the justice and mercy of God may be glorified. This will not pain or embarrass the saints, but add to their glory, just as the repentance of St. Peter and St. Mary Magdalen is to these saints a source of joy and honour.

With the fulfilment of the sentence pronounced in the last judgment the relations and the dealings of the Creator with the creature find their culmination, are explained and justified. The Divine purpose being accomplished, the human race will, as a consequence, attain its final destiny. The reign of Christ over mankind will be the sequel of the General Judgment.

Thus, while the particular Judgment make judgment on our eternal destiny, the Last Judgment examines our lives in detail not to judge whether or not we go to heaven or hell since that has already been determined, but to fulfill justice in the public forum and to assign final rewards and punishments.

All those in heaven will go to the Final heaven prepared for them. All those in hell will go to the final hell prepared for them. The New Heaven is mentioned in the Bible (Rev. 21.1). I believe the word Gehenna, one of several words in the Bible referring to hell, is the final hell.

God Bless,
Bro. Ignatius Mary