The Saints captain featured for the first 73 minutes at Wembley, and did his chances of playing a key role in Brazil this summer no harm at all.
England now fly to Miami for friendlies against Ecuador and Honduras, before jetting to South America, with their opening World Cup fixture, against Italy, taking place on June 14.
Lallana is hoping to retain his starting berth for that game.
“I was delighted (to start). Obviously, getting in the starting line-up for the first game in Manaus is what everyone’s striving for, and hopefully I’ve done enough to impress the manager and show him what I’m capable of,” he said.
“It was a good result and we move onto the next game.”
Lallana, who was not allowed to talk about club matters, added: “It’s been a great week, a hard week’s training, a good bit of fitness, wearing layers to try and adapt for what we’re coming into.
“The weather’s not been too kind to us this week, but the fitness of everyone is looking good.
“We haven’t picked up any injuries, so that’s the main thing. We’ll recover and fly out to Miami on Sunday.
“It’s a big week, we’ve got two big games out there in tough conditions, so we’ll look to put in a couple of good performances like we did today.”
Lallana said he was excited about the prospect of what lies ahead, although admitted it is still hard to totally get his head around.
“It’s a strange feeling, you just want to take it all in, but it seems to be happening so quickly,” he said.