tempo and moving same piece twice

When the enemy brings their queen out early in the game, such as on turn 2, I feel conflicted about the rule for not moving the same pieces twice in the opening. Are you supposed to repeatedly threaten the queen no matter what, even if it means moving the same piece twice?

I lose if I attack the queen and I lose if I develop pieces. It feels like early queen attacks are extremely specific in how you must defend against them. Like there's only one correct move.

not exactly

As for the wayward queen attack, the only correct response is to defend your pawn with the knight, isn't it?

If your opponent brings out the Queen early, then simply develop your pieces. Often times you can develop a piece AND attack their Queen. While they are forced to move the Queen again, you gain a turn (tempo) to do something else (like develop another piece). Usually these early Queen moves are discouraged because the player usually suffers from a lack of development (since they constantly need to attend to their Queen); additionally, there are many pieces on the board at the start of the game and as follows more ways a reckless Queen may get itself trapped. 

Do not simply attack their Queen if it can go to a better square, but attacking an early-venturing Queen often develops your forces with initiative and gain of time. 

p.s. just be careful for quick checkmates against you. The pieces are poorly coordinated at the start of the game, so an early Queen venture does attack a potential weakness in your camp. However, if you know how to combat these Queen-raids early on then you are often left with at least some advantage (usually in development). There is not one "right move" to fight these Queen-raids, but these Queen ideas early on should be taken at least somewhat seriously. Simply develop and you may find yourself in a pleasant position. Trying to "punish" your opponent immediately sometimes works, but should often be avoided. Why "punish" your opponent with a piece or two now, when your entire army can swarm in later on?

 What is important to remember:  You want your opponent to react to you, you don't want to have to react to your opponent.

IMBacon, nice post (#11). 

This is a more thought-out response than mine (There's subtle humor in there; I like it  )

As I mentioned earlier, early Queen ventures should not be anything to fear and there are certainly multiple well-accepted ways to approach this threat. IMBacon and I highlighted only a few of these here. Many acceptable variations exist and subtle differences should be chosen by preference as different approaches work for different chess players. 

Thank You Sir!

I work with kids, and beginners a lot.  And as usual, these types of things strike fear into the hearts of the beginner.  I know it did me, when i started.  This is why i try and instill n them "Make your opponent react to you, not you react to your opponent"  Which is why i like 2.Nf6.  But i let the kids know that there is nothing to fear here, and how to deal with it.

I'm confused again lol

Re-read post #11, and play through the 2...Nf6 line. 

I looked at it just now. That causes you to be behind one pawn and both sides have 3 pieces developed. It doesn't seem favorable to me

is there a better place white could put his queen instead of 5.Qf4 ?