If you have created a net-new Active Directory domain then you are going to have to re-add all of your computers/servers/printers/etc back into this new Domain regardless of the name being different. This is also because you have different SID from the previous domain.
Seems like you have a lot of work ahead of you. Make sure that as soon as you get the DC up and running that you add an additional DC to ensure resiliancy.
Will.