The young midfielder saw action in the FA Cup win over Derby County.
"It's sunk in now," he told chelseafc.com.
"I keep thinking back to it, and it was probably one of the best things that has ever happened to me. Jose Mourinho just said good luck and enjoy the experience, while every single player has been great to me as well.
"They've been helping me along and giving me lots of advice, telling me to just play my normal game and try and enjoy the experience.
"I've played in massive games like the Youth Cup finals, the Next Gen tournament where we played Barcelona and other top European teams, but this was different, playing with some of the best players in the world, the stadium was packed and it was just a great experience."