Did you introduce them in neutral territory, not your house? That's the best way to introduce two dogs for the first time.
Except for the peeing, you didn't say that you had any problems with them so I'm not sure what the question is.
It will take awhile for them to become friends. Don't push it. Let them work it out for themselves. Of course you'll have to keep them separated until you are absolutely certain they will be fine together.