Or in other words: do i have to look in my discard pile if there is an Ally, which i played this turn ?
You would not consider cards in your discard pile. During the course of your turn, as you play cards you do not put them into the discard pile. Keep played cards separate from your discard pile until you finish your turn and do cleanup. Newly acquired cards do go to the discard however.
The way we were taught at the FFP booth at Gen Con is that you essentially play your entire hand to your board, then decide how you're going to use the resources and abilities. In that case the timing of how many allies you have played when you defeat Timber Wolves would not come into play - you would consider them to all have been played. But I think you could play that timing to your personal taste and only count those you have used to acquire any cards previously that turn.