Lost XP account

Hi recently I got a new laptop and wanted to transfer my songs. Well the Laptop and my Deasktop(The one with the songs). Were not on the same workgroup. So I put it on the same workgroup. I went to my computer then properties and then computer name. Then I THINK I might have went into network ID ands changed something regarding the I am runnig on a home network or I am running on a business network. Anyway I don't remeber. Then I changed the workgroup name to Home and changed the computer name to JessPC. Then I restarted the computer and My account went missing. What showed up was my last name which I have never seen before so I clicked on that account and it was "setting up" Themes, Internet explorer Outlook, etc. And the name of my other account was Administrator. So where did "Administrator" go? I also checked C:\Document's and settings and the account is still their.

OS: WIndows XP