instead of a desoldering "tool" get some of this stuff
http://www.radioshack.com/product/in...entPage=search
used with a small iron (NOT A BIG GUN). carefully remove the wire you just attached ( we need to fix it up a bit).
Take the braid and lay in on the circuit board and apply the iron tip. It will absorb the excess solder. If there is too much solder, snip off a section of the braid and reapply. Remember to not apply the heat for too long and to allow the board time to cool between heatings so you won't damage the electronics. That one solder blob might "pop" off with a GENTLE prying but don't push the issue. Use the braid if needed. When done with the braid you will see that it has left a thin tinned film on the contact, CAREFULLY add a little more solder to that contact pad but NOT a lot.
Now for the wire. If the end has become mangled looking it would be best to just cut off a 1/4 inch or so and start over, otherwise gently warm the wire and when the solder flows you can "tap" the excess solder off the end. Be careful as it may splatter. If you cut the wire you need to strip back the insulation about the same amount as the other wire, be careful not to nick ANY of the inner wires or to "un-nest" the wires when you slide the insulation off. Use the iron and solder to "tin" the wire careful to not overheat and damage the insulation, have enough solder though so it will be able to flow to the board.
Now find a third hand, a friend or wife or mother whatever. You need help for this.
Have them hold the wire in place on the board contact while you apply the iron to melt the solder. They need one hand on the board and one on the wire. You need one on the iron and a second to hold solder in case you need more. Do not apply so much pressure that you squash the wire when the solder flows and do not add so much solder that it is excessive and do not overheat the board.
After soldering, remove the iron but hold the wire in place until solder cools. It should cool to a bright finish. If it is dull, pitted or "crackley" then the wire moved during cooling. Gently reheat.

good luck, that should do it if no damage was done before.