Unable to login to a domain computer using a Local Administrator account

I have a server running on windows server 2008. Recently we created a domain and added it to the domain. Also it is promoted as an additional domain controller on the network. A domain user account was created with same username and password as my previous local administrator account. Now I unable to login using my local account. I tried loggin in using SERVERNAME\Username, but it is giving incorrect password error message. Is there any way I can retrieve or create a new local administrator account on a domain computer

Is the machine a Domain Controller? If so, you lose the ability to log in as a local account. You would have to demote the DC in order to log in as a local account.

Domain Controllers do not have local accounts. They "become" the domain in many ways. If you need settings or files from the old profile, it should still be in the Users directory.