Armando Broja says his form with Albania U21s helped establish himself at Chelsea.
Broja is now on-loan with Vitesse.
He told Goal: "In the first year of U18s, I was 17 and I wasn't having the greatest season. I scored two goals all season so I was really down.
"I was even missing shots in training, so I didn't play a lot. Then, I had a boost from my mum and dad that Albania called me to play with them in the summer.
"It was the U19s, so I thought it would be good to go there and get some confidence, in a different team with different players, to get my mind away from Chelsea where the season wasn't the best. I went to Albania, played four games and I scored six goals so I felt good.
"I was scoring, playing well and Chelsea saw it. Before the start of the season, I played in Albania's U21s against Wales in my debut. I came on at half-time and I scored within two minutes of coming on. I scored again 10 minutes later and I was feeling good and sharp and we were winning 2-0. I came off and we won.
"I felt good and I had a big confidence booster. I felt really good in pre-season with Chelsea and they saw what I achieved ahead of my second year of the youth team. I really hit the ground running and I made sure it was a good year for me.
"I went there and I scored two goals in each of my first two games and carried on scoring. It kickstarted and continued until I am here now. It is good I had that period going down to go back up. You learn a lot in that time that it is not always easy."
He added: "To be a full international at 19 is something many players have done but also a lot of others haven't done. Yes, it is good because as a player from Chelsea, they also expect a lot from me in Albania."