The Arsenal midfielder was left crumpled in a heap on the Wembley turf following a tough tackle from Daniel Agger that required treatment and briefly stopped play.
Wilshere carried on playing before eventually making way for Adam Lallana just before the hour mark, with the 22-year-old quick to play down fears he sustained any lasting damage from his tangle with the Liverpool defender.
"I'm fine," he insisted to Sky Sports. "It's a bit sore but it's only a bruise. I've had a scan already and it showed just a bruise so I'll be alright."
England was far from its best at Wembley - with Daniel Sturridge's goal proving decisive - but Wilshere believes that there are positives to take from a below-par performance as the World Cup edges ever closer.
"We kept going and got the goal in the end," he said. "When it comes to the World Cup, those crucial goals at the end are going to make a big difference."