If you get really lucky, you could get two lol. Happened to me when I decided to go for the 1k guaranteed, got an extra one on spin 13 or so and it doesn't reset the counter.

You can get a gold essence without having maxed the x/20 counter. When the counter is at 20/20 you are guaranteed to get the jackpot (in this case the gold essence) on your next spin. It is however still possible to get the jackpot without maxing out the counter, which is what happened to me somewhere around my 13th spin.