Nostalrius Begins - Quality wow vanilla realm (1.12)

On my Night Elf I find that the hand in dialogs for quests close/the continue button is activated within a second of opening. It only stops if there is a choice to be made: aka choosing a reward.

Is this a common occurrence, it doesn't seem to happen on my other character.

That is not common. I'm wondering if instant quest messages is bugged for you somehow.

I did have them on when I created this char. I have since turned them off but it still occurs. I might create a new char with them off and see if it happens. Although this didn't start right off the bat. It started a day or two into this character.

If you have any quest addon, like Rapidquest or Extendedtracker than I would advice you to look in settings if :"Automatic Completion of quests" is checked.
I have this and it happens to me only if that option is checked.

oh! I shall definitely look at that!

edit- yes, that was it, thank you.