I have XP Pro hooked up to my linksys router at the house.
I tried to login to my PC from mom's pc (also XP Pro) with my IP but it won't let me login.
I configured XP thanks to google but I can't find instructions for my linksys router.

Here is what the message tells me.....

( X ) The client could not connect to the remote computer.

Remote connections might not be enabled or the computer might be too busy to except new connections.
It is also possible that network problems are preventing your connections.

Please try your connections later. If the problem continues to occur, contact your administrator.

I remote desktop between computers at my house and I've got a Linksys router, the only port I am forwarding is 3389.

Next retarded question...
How do I check my port and How do I configure it to windows if it's different?

I'm not sure exactly what you are asking.

Perhaps this will help http://support.microsoft.com/kb/306759