Problem loggin into phpmyadmin and webpanel

well i have already submitted a support ticked for this problem twice but its been 24 hours and no reply yet and I am very anxious to get my site up and running so I will ask here.

I already have a host where my website is running live currently
I signed with dreamhost about 3 days ago and my account has been activated.
But the problem is that I choose “I already have a domain” and specified my domain (as the one currently being used by the other host). I cant transfer it over yet to dreamhost because that will mean site going down completely for a few hours which I dont want.

So when I log in to webpanel via dream host…it takes me to the account on my other host

when I try and log in to phpmyadmin (so I can restore my database from the other host to this one) I cant login with any of the specified servers!

What am I to do ? Please help since I am pretty new to all this dns / domain stuff and now im totally confused!

I really need to have my database restored and my site is already uploaded on dreamhost! But I cant take it live until I can restore AND test it on dreamhost!

someone help!