The 18-year old was getting set for a college season with Creighton University before he tried his luck in the UK with what ended up being a successful trial with the Rams.
Doyle has broken into the first team at Pride Park but admits it has been a bit of a blur in the past few months.
"It's been a whirlwind," Doyle said. "It's been crazy. I was preparing for my first college season, and all of a sudden I'm playing in my first Championship season.
"I definitely didn't expect to be doing this at 18. I really wanted this to happen, and I hoped it would, but I never thought it would happen at such a young age."
Doyle admitted that the move had been made a lot easier because of his Derby teammates and said he was very keen to getting on the scoresheet for his new club.
"It's working out really well right now," Doyle added. "The guys have been fantastic and so welcoming. They made it a second home already.
"It'd be great to just put one in. I put that pressure on myself. Whether I'm 18 or whatever, if I'm out there I want to score. I really hope that first one comes soon and there's more to follow."