"I was ready, I trained with the squad, all the boys have helped me settle in really well," said Gilmour.
"To play against England in my first game, I’m so proud and to come here and do really well was even better.
"It gives us massive confidence against Croatia. We go back to the hotel to recover and then focus on them.
"I found out [I was starting] in training before we travelled down, we had a slight idea – we were doing shape and set pieces – but it wasn’t until the last meeting before the game we found out the team.
"My mum and dad only knew I was starting, I text them on the bus to the game and that was it.
"I had mum, dad and little brother, uncle and my dad’s mates [at Wembley]. My mate as well, he came down. I got them tickets. It was a good moment."
There were around 2,700 Scotland fans in the 20,306 spectators at the national stadium and Gilmour continued: "[To hear the fans singing my name] was amazing, the fans were incredible as well, singing from the first minute to the last.
"They gave us a massive boost. We knew we had to go on the pitch and give the fans what they wanted.
"They stayed behind [at the end], we went over they were amazing. We were already pumped up, motivated for this game. It was a massive game and we knew what we had to do. All the fans will be at Hampden [for the Croatia game], it was a great atmosphere the last game at Hampden, so it was. That one is going to be massive. We need to be prepared for Croatia.
"This game is definitely up there," he added. "Playing for my country, I’m so proud, against England as well at Wembley. It’s massive.
"We go back, recovery, fully focussed on Croatia now. We know what we need to do to qualify from this group. That’s it. Back to the hotel to start again."