Majoras Mask questions

[Dasbreenee]

So I've never played it. Just started it a bit ago.
I'm just... Confused?

I retrieved the Ocarina. Set the time back. Which I understand goes back 3 days.
Now, when I set the time back I'm being told the Fairy has something special. But when I go talk to her, she just wants me to go get the fairy again.
Do I just have to keep doing everything over and over? Or what?
Also, when three days happens and it starts to get near the end do I need to set time back again?

 

[spCrossing]

When you get the Stray Fairy from Clock Town the 2nd time and also turn back into regular Link, you'll get the Great Fairy Mask which makes getting the Stray Fairies in Dungeons easier than before.

 

[Earth Wolf-Howl]

Do I just have to keep doing everything over and over? Or what?
Also, when three days happens and it starts to get near the end do I need to set time back again?

1. Not necessarily. The example with the Great Fairy is a demonstration of the mechanics of time: everything is returned to normal. However, you don't need to re-do absolutely everything to complete everything: in future cycles, you can ignore the Great Fairies; troubled regions (unless you need to repeat them for sidequests), everything like that.

2. You do need to go back to avoid a Game Over, yes, but you can keep every Rupee you collect in the bank (don't ask) and important items like dungeon items, masks and Heart Pieces. Consumables like keys and unstored Rupees are lost, though.