Most of New Zealand's elite young golfers come through the age-group representative system and compete at the main amateur tournaments from their early teens.
But Charlton's passion and ability in hockey and cricket has meant golf was a sideline for him until this year, when his career began taking off.
"I first started with the Bay of Plenty this year and have just been named as captain of the under-19 team, so that should be a good experience. The manager told me that if I keep playing the way I am, there is a chance I could go away with the senior team (to the nationals) for experience.
"I have never really put together a big performance before. I have been on a three or four handicap for a few years but this year is a first for me playing big tournaments like the NZ Amateur.
"I made the cut at the North Island Men's and North Island under-19s then, of course, the New Zealand under-19s when it all kicked off for me."
Charlton pushed eventual winner Tyler Hodge all the way at the national event held earlier this month at Northland's Waipu Golf Club, before losing by a single shot.
The tournament was in his hands after he fired a brilliant birdie at the 15th, but he dropped two shots in the final three holes.
It was an exceptional performance and the first time Charlton had played in the final group at a major event.
"It was just really cool playing off last because I had never been in contention to win a big tournament. I got off to a good start by birdying the first hole, which eased the nerves a bit, but the last three holes were playing tough.
"Tyler has won the last three tournaments he entered so competing with people like him has been great and proves all the practice is paying off.
"Having my coach there (Jay Carter of Golf Fusion) was really helpful because it made me feel much more comfortable. He has been huge in my development. My swing and everything at the start of the year was up in the air, not good.
"Jay has been a good mentor..
The key thing I have learned from that experience (at Waipu) is I know I have the ability to do it. I always believed in myself but no one really believed in me. I knew it was there but had not previously put four rounds like that together."
Charlton will take his new-found belief and confidence into this week's Carrus Tauranga Open, where he is hoping to make another major impact.
"Being the top amateur is my ultimate goal. I want to be under-par for the tournament and now I know I can do that, I am going to be pushing hard to achieve that."