Does the Eternal Age start before or after the Millenium?

I ask this questions because most Christians believe that the Eternal Age begins AFTER the millennium. There are few out there who say that it starts BEFORE the millennium, including myself. I want to here your opinions on this.

 

What I meant is: when do the new heavens and new earth begin?

 

That makes sense, but why is it that Isaiah links the new heaven and new earth BEFORE the millennium?
Notice Isaiah 65:17-25, "17 “For behold, I create new heavens and a new earth; And the former things will not be remembered or come to mind.
18 “But be glad and rejoice forever in what I create; For behold, I create Jerusalem for rejoicing And her people for gladness.
19 “I will also rejoice in Jerusalem and be glad in My people; And there will no longer be heard in her The voice of weeping and the sound of crying.
20 “No longer will there be in it an infant who lives but a few days, Or an old man who does not live out his days; For the youth will die at the age of one hundred And the one who does not reach the age of one hundred Will be thought accursed.
21 “They will build houses and inhabit [U]them[/U]; They will also plant vineyards and eat their fruit.
[B]22 “They will not build and another inhabit, T[B]hey will not plant and another eat; [B]For as the lifetime of a tree, [I]so will be[/I] the days of My people, [B]And My chosen ones will wear out the work of their hands.
[B]23 “They will not labor in vain, [B]Or bear [I]children[/I] for calamity; [B]For they are the offspring of those blessed by the Lord, [B]And their descendants with them. [/B][/B][/B][/B][/B][/B][/B][/B]
24 “It will also come to pass that before they call, I will answer; and while they are still speaking, I will hear.
25 “The wolf and the lamb will graze together, and the lion will eat straw like the ox; and dust will be the serpent’s food. They will do no evil or harm in all My holy mountain,” says the Lord.

Clearly he is talking about the Millennium kingdom in these verses. But notice how God say that he creates a new heaven and new earth before all this occurs. Could it be that the millennial Kingdom is the begin of the new heaven and earth? Could it be that the New Jerusalem comes down in the begin of the millennium as opposed to the end? I think this is very possible.