Just go into LW's tools > options > advanced > firewall config & untick that manual port forward button > apply. If you want to, you can go log back into your router & remove the rules you created in there too.
Did you make sure that LW's listening port & the port forwarded were the same number?

It sounds like you did something wrong along the way somewhere...port forwarding is usually very reliable. But if you don't want to try again that's fine, it is a bit of a fiddly thing to set up.