Wilshere fractured his foot during England's 1-0 friendly win over Denmark two months ago and has been restricted to just two substitute appearances so far in his comeback.
But the 22-year-old has still been included in the 23-man squad for the World Cup, which starts next month, and was pleased to have received a show of faith from England manager Roy Hodgson.
"I was nervous. I would have been devastated if I hadn't gone. But it's a great feeling," Wilshere told The Sun.
"It wasn't a call, it was a text. I was at home, it was a great feeling.
"I wasn't fit towards the end of the season, so it was a bit touch and go.
"I think the boss at England knew that - but he had been speaking to (Arsenal manager) Arsene Wenger and he came to the decision that I should go. I'm delighted."
"I'm not match fit. The only way you get match fit is by playing matches," he added.
"So I'm as fit as I can be without playing matches.
"I've done as much as I can, now I just need a few games. It's a different kind of fitness - it comes back quickly.
"If I play in a few of the friendlies, I'll definitely be match fit."
