Is it possible to tear the vagina during sex? If so, what can you do to fix/relieve pain. This isn't the first time having sex.

Possible,unlikely. While it is possible, it is unlikely unless your intercourse is particularly rough or you are using large or rough toys. If you did have a tear, you should be seen by your gynecologist. Just because you are asking, you are concerned. You should be talking with your gynecologist about this and especially methods of birth control. You should discuss these issues to make sure that you are safe.