I suffered 3rd degree tearing with my first. Things were different down there afterward. Not bad as such, but definitely different. I didn't even try to DTD until about 6+ mths after having DD. It was different afterward, and required lots of lube, but better in some ways and worse in others.

I have gone on to have 2 more births with no tearing what-so-ever, just a little grazing with one of them. So tearing once does not mean tearing again.