I would redo the soldering job. You can get it off easily by touching where it is currently soldered with your soldering gun, and then pulling away *gently* while the solder is still hot.
Wipe away whatever of the solder you can with a wet sponge, wipe the wires dry and then try again. :)
Oh yeah... And do that while it's not plugged in as well... We don't need any electricution possibilities :)