This is the bulk of my rare mount 'stories'.
Not quite your luck but pretty darn decent for a couple of hours.
Got a mount on my first Warbringer kill, 2nd one on the 4th or 5th kill and finally got my 3rd one about a week ago after countless kills, working on my 3rd Egg Raptor while collecting bones for the white one (+-6k atm).
Also, just yesterday I got my archy Battle Tank after a 5 day grind, nearly had a heart attack when it popped...